Current Issues in Chronic Diseases: A Focus on Dementia and Hypertension in Rural West Texans

Abstract

Dementia and hypertension are chronic diseases that affect elderly populations worldwide. The prevalence of these diseases increases each year, especially in rural and underserved rural communities like West Texas. The purpose of this study was to find risk factors of dementia and their impact on rural West Texans. Data was provided by the Project FRONTIER for rural West Texas counties. The SPSS software package was used for statistical analysis. Pearson’s chi-squared test was also utilized to determine the relationships between the risk factors considering a level of significance (α) = 0.05. The findings have shown that age group had significant associations with hypertension, cerebral, neurologic disease, Romberg test, and muscle strength for both males and females (p≤0.002). Hypertension was significantly associated with cognitive disorder and diabetes in both males and females (p≤0.011). Age group in females was significantly associated with parkinsonism (p = 0.02), neurological stroke (p = 0.002), reflexes (p = 0.003), and sensory intact (hands/feet) (p = 0.004), respectively, whereas age for males was not significantly associated with those variables (p = 0.29, p = 0.05, p = 0.56, and p = 0.76, respectively). Hypertension in females was significantly associated with cardiovascular disease (p = 0.001) and depression (p = 0.001) but was not found to be significant for males (p = 0.30 and p = 0.09, respectively). Both males and females in Hispanic and non-Hispanic groups were found to be significantly associated with Alzheimer’s disease (p = 0.0001 and p = 0.045, respectively). Hispanic and non-Hispanic females were found to be significantly associated with hypertension (p = 0.026). Gender-specific differences in dementia risk factors exist and integrating such variables may guide relevant policymaking to reduce dementia incidence in rural West Texas.

Keywords

Cardiovascular disease cognitive disorder dementia FRONTIER database hypertension statistical methods

INTRODUCTION

Dementia is a global and chronic clinical syndrome characterized by symptoms of memory loss, language disruption and communication skill degradation, behavior changes, and impairments in daily activities and cognitive function. Alzheimer’s disease (AD), a neurodegenerative and progressive disorder, is the most common form of dementia in the elderly and can comprise 60% to 80% of cases [1]. In 2015, the Global Burden of Disease Study shows approximately 46 million individuals have been impacted by dementia, and dementia is rising rapidly among elderly populations worldwide [2, 3]. Predictions show that by the year 2050 more than 100 million individuals will be impacted by memory loss [4]. The incidence of AD tends to be lower in less economically developed countries than in Europe and North America. However, sharp rises in prevalence of AD has been both predicted and seen in countries like India, China, and Latin America [5]. To address the growing dementia epidemic, almost all projections, including those published by the Alzheimer’s Disease International (ADI), assume that age and specific age prevalence will not vary over time and that population aging alone can drive the projected increase [6]. At the national level, over 5 million adults in the United States are living with dementia, which can have a large social and economic impact and burden on patients, families, and government programs [5]. The total costs associated with dementia were estimated to be $226 billion with Medicare and Medicaid programs providing 68% of funding. Additionally, out-of-pocket expenses for patients and their families were expected to total $44 billion. In Texas, AD affects approximately 390,000 individuals, and Texas ranks fourth in the number of AD cases and second in the number of AD deaths. AD places a tremendous burden on the Texas healthcare system because in 2018, approximately 1.6 billion hours of unpaid AD care cost approximately $20.6 billion [7]. There are many diseases that can also influence the risk of dementia in elderly patients. They include and are not limited to diabetes, cardiovascular diseases (CVD) like coronary heart disease (CHD), depression, etc. Type 2 diabetes was found to be a predictor of cognitive impairment and decline in older adults. Multiple population-based studies have shown that older adults with type 2 diabetes experience global cognitive decline at a rate over 5 years double than those without diabetes [8]. Another meta-analysis of 28 observational studies showed a 73% increase in all-types dementia and a 56% increase in AD in patients with a history of diabetes as compared to non-diabetics [9]. Additionally, a meta-analysis of 10 prospective cohort studies have shown that individuals with CHD have, on average, a 45% higher chance of developing cognitive impairment or dementia. However, the exact mechanism by which CHD leads to dementia is still unknown and requires further research. Other types of heart disease contribute to cognitive decline and dementia risk, most notably, atrial fibrillation.

Individuals with AD can present non-cognitive symptoms like depression, psychotic symptoms like hallucinations or delusions, and behavioral symptoms like aggression and motor hyperactivity. Additionally, AD is not just characterized by problems in memory, but also in visuospatial abilities whereby individuals can become lost even in a familiar environment [2]. It is also important to understand that from a public health perspective, depression is not just a predictor of dementia but also a comorbid condition that will develop during its course [11]. Results of a study conducted by Snowden et al. [11] demonstrated significantly higher rates of depression in cognitively impaired individuals. As such, community-based interventions for treatment of dementia can be prepared to address depression and significantly reduce its symptoms.

Hypertension is another chronic disease and an important global health challenge because of its high prevalence. It is also the leading preventable risk factor for premature death and disability worldwide [12]. Since the year 2000, the number of individuals with hypertension has increased by 466.8 million, with a 26.6 million increase in high income countries and a 440.1 million increase in low and middle income countries [12]. At the national level, about 75 million Americans suffer from hypertension, with only about 54% of individuals with hypertension controlling their disease. Like dementia, individuals with hypertension place a burden on the healthcare system while also decreasing economic productivity. Hypertension costs the nation approximately $48.6 billion each year. This figure includes the cost of healthcare services, medications, and missed days of work [13]. In Texas in 2018, 31.2% of females and 33.8% of males were diagnosed with hypertension. The female percentage was actually higher than the US national average of 30.4%, highlighting the problem for Texas [14]. Also, treatment and control of hypertension are essential in preventing subsequent diseases, and some studies have even shown that there is a link between hypertension and dementia. For example, one study showed intracranial hypertension was linked with AD in the 60–65 and 70–80 age groups [15]. Although intracranial hypertension is not common among elderly individuals, the association between intracranial hypertension and AD has been demonstrated. Additionally, repeated episodes of intracranial hypertension, such as those caused by head injuries or conditions like heart failure, may be a triggering factor for AD. In the comprehensive review on hypertension and dementia, Turana et al. [16] stated that most investigators were not aware of the correlation of dementia and hypertension.

By the year 2030, approximately 520 million individuals will be impacted by dementia in Asia, as cognitive impairment increases with age. This was demonstrated in another study conducted by Abell et al. [17] where they found that high systolic blood pressure at age 50 was associated with an increased risk of dementia. The excess risk in this study was seen around 130 mmHg which is just slightly elevated from the normal blood pressure range, and longer exposure to hypertension increases dementia occurrences. Also, hypertension is known to have serious effects on the brain, as damage in the brain can lead to memory loss. Wändell et al. [18] found that although hypertension is one of the factors contributing to dementia, depression, diabetes, atrial fibrillation, and other such coronary heart diseases are more crucial factors in impairing memory. In a study with a sample size of n = 537,513 for elderly patients ≥45 years, hypertension was one of the factors which was not significantly associated with dementia in either gender; the quality of medication and antihypertensive drugs was postulated to have a protective effect [19]. Walker et al. [20] describes how changes in cranial functions can occur due to hypertension, which can ultimately lead to reshaping the cerebral vessels. Iulita and Girouard [21] discussed how hypertension can lead to AD and cognitive impairment. Some researchers say that more tests need to be done on antihypertensive drugs and whether they really can serve as a preventive measure of dementia. In a study conducted by Boockvar et al. [22] with a sample size of n = 255,670, individuals that received antihypertensive drugs had no significant results of reducing hypertension.

Ethnicity may be defined by whether a person is of Hispanic origin or not and it can be classified into two categories, Hispanic and Non-Hispanic. In Texas, the Hispanic population increased from 9.7 million in 2010 to 11.1 million last year. Meanwhile, the White population has only increased by about 458,000 people. With growth among the Hispanic population in Texas continuing to easily outpace growth among White Texans, it is likely the state will reach that demographic milestone as soon as 2022 [23]. There were no published works available in peer-reviewed journals in relation to the focus on Hispanic and non-Hispanic ethnicities in rural West Texas. Thus, it is essential to understand ethnic-based risk factors influencing dementia in rural West Texas. This paper aims to explore the risk variables of dementia and hypertension related chronic diseases from four rural West Texas county data collected by Project FRONTIER (2006–2018).

METHODS

Project FRONTIER

Initiated in 2006 as the Cochran County Aging Study, Project FRONTIER (Facing Rural Obstacles to Healthcare Now Through Intervention, Education & Research) is an epidemiological study exploring the natural course of chronic disease development and impact on longitudinal cognitive, physical, social, and interpersonal functioning in a multi-ethnic adult sample from rural communities of West Texas. Any person who was 40 or above and lived in one of the participating counties was eligible to participate. Project FRONTIER has participants in Cochran, Parmer, Bailey, and Hockley Counties (Fig. 1).

Fig.1

The four rural west texas green highlighted counties used by project FRONTIER.

IRB approval

This study protocol was approved by TTUHSC IRB (Texas Tech University Health Sciences Center, Institutional Review Board) NUMBER: L15–158; IRB APPROVAL DATE: 07/06/2015.

Sample size and power calculation

The sample size was calculated by using G^*Power software (version 3.1.1) [24]. A total of 88 subjects was sufficient to detect a statistically significant relationship between categorical variables with a level of significance alpha (α) = 0.05, median effect size = 0.30, and power = 80% when running a chi-squared test. The study used a sample of > 100 participants to assure power for determining relationships between variables.

Statistical analysis

SPSS software (version 25.0) [25] was used to perform statistical analysis. The statistical method of Pearson’s chi-squared test for categorical variables was also used. Alpha level (α= 0.05) was used to determine statistical significance. This method was performed to calculate odds ratios (OR), 95% confidence intervals (CI), and to determine an association between risk factors.

RESULTS

The data from the Project FRONTIER were used for statistical analysis by utilizing SPSS software and the results are given in the text, tables, and figures format.

There were 184 male participants that were asked whether their brother had any symptoms of dementia and hypertension. The results showed that the majority of participants, 130, had no symptoms of either diseases and 51 had hypertension and no dementia. There were two participants that had hypertension and dementia. One participant had dementia but no symptoms of hypertension. The statistical method chi-squared test was performed and found that there was no significant association between dementia and hypertension (p = 0.14).

Of the 410 total female participants that were asked whether their brother had any symptoms of dementia and hypertension, 285 had no symptoms of either disease and 118 had hypertension and no dementia. There were four that had hypertension and dementia, and three that had dementia but no symptoms of hypertension. The chi-squared test was conducted and found that there was no significant association between dementia and hypertension (p = 0.11).

There were 142 male participants that were asked whether their grandmother on their father’s side had dementia. Of the 142 participants, there were 133 who responded no and 9 that responded yes. The chi-squared test was performed and found that there was no significant association in males between their grandmother on their father’s side having both dementia and hypertension (p = 0.48). Of the 311 females that were asked the same questions, 293 responded no and 18 responded yes. There was no significant association in females between their grandmother on their father’s side having both dementia and hypertension in females (p = 0.39).

To determine whether males develop dementia relating to hypertension, 172 were asked whether their sister had any symptoms of dementia. To find association of these participants with hypertension, it was found that 133 of them had no hypertension and no dementia; 37 had hypertension but no dementia reported. There was no significant association found for dementia and hypertension in males (p = 0.46). Among the 405 total female participants that were asked the same question, thorough diagnosis found that three were hypertensive and had dementia, and 8 had no hypertension but developed dementia. Of the 394 females, 268 had no hypertension and dementia, and 126 had hypertension but they have not yet developed dementia. There was no significant association found for dementia and hypertension in females (p = 0.74).

Table 1 shows the age groups and hypertension for the study participants. Three categorized age groups, 40–64, 65–84, and ≥85 years of age were defined for a total of 461 males. Among the age group of 40–64 (n = 278), 132 males did not experience hypertension and 146 males did. In age group 65–84 (n = 168), 39 did not show symptoms of hypertension whereas 129 did. In the age range of ≥85 years of age (n = 15), 12 had hypertension and 3 did not. There was a significant association found when comparing the age groups to hypertension for males (p = 0.0001).

Table 1

Age and hypertension for males and females

	Hypertension
	Male				Female
Age	No	Yes	Total	p	No	Yes	Total	p
40 to 64	132	146	278	0.400	379	334	713	0.090
65 to 84	39	129	168	0.001	92	224	316	0.001
>85	3	12	15	0.020	4	14	18	0.010
Total	174	287	461	0.001	475	572	1047	0.002

Out of a total of 1047 female participants in this study, three age groups were used, and they were 40–64, 65–84, and ≥85 years of age. In the age group 40–64 (n = 713), 334 had hypertension and 379 did not. In the age range 65–84 (n = 316), 224 had hypertension and 92 did not. In the age range of ≥85 years of age (n = 18), 14 had hypertension and 4 did not. Overall, in the case of females, it was found that there was a significant relationship between age groups and hypertension (p = 0.0001).

There was no significant relationship between AD and age groups for both males (p = 0.07) and females (p = 0.33). There was also no significant relationship between dementia (whether uncle on father’s side had such problem) and age groups for both males (p = 0.57) and females (p = 0.30). There was a borderline significant relationship between neurological-stroke and age groups for males (p = 0.05) and a significant relationship for females (p = 0.002).

There were 3, 3, and 1 males (n = 401) with symptoms for neurological-parkinsonism for the age groups 40–64, 65–84, and ≥85, respectively; in males there was no relationship between parkinsonism and age groups (p = 0.29). There were 3 and 7 females (n = 904) with symptoms for neurological-parkinsonism for the age groups 40–64 and 65–84, respectively; in females a relationship was found between parkinsonism and age groups (p = 0.02). There were 3 males (n = 401) with parkinsonian rigidity observed for the age group 65–84 and > 85, respectively. There were 2 and 1 females (n = 901) with parkinsonian rigidity observed for the age groups 65–84 and > 85, respectively.

There were 3, 7, and 2 males (n = 401) with abnormal neurological-cerebellar diagnoses for age groups 40–64, 65–84, and ≥85, respectively; a significant relationship was found between abnormal neurological-cerebellar diagnoses and age groups (p = 0.001). There were 6, 12, and 2 females (n = 898) with abnormal neurological-cerebellar diagnoses for age groups 40–64, 65–84, and ≥85, respectively; a significant relationship was found between abnormal neurological-cerebellar diagnoses and age groups (p = 0.001).

There were 6, and 6 males (n = 401) with neurological-reflex abnormalities diagnosed for the age groups 40–64, and 65–84, respectively; in males no significant relationship was found between neurological-reflex abnormalities and age groups (p = 0.56). There were 9, 10, and 2 females (n = 903) with neurological-reflex abnormalities diagnosed for the age groups 40–64, 65–84, and ≥85, respectively; in females a significant relationship was found between neurological-reflex abnormalities and age groups (p = 0.003).

There were 17, 31, and 5 males (n = 401) unable to rise from a chair diagnosed for neurological-rising for age groups 40–64, 65–84, and ≥85, respectively; a significant relationship was found between rising and age groups (p = 0.001). There were 46, 52, and 9 females (n = 903) unable to rise from a chair diagnosed for neurological-rising for age groups 40–64, 65–84, and ≥85, respectively; a significant relationship was found between rising and age groups (p = 0.001).

There were 11, 21, and 3 males (n = 398) with abnormal neurological-Romberg tests for age groups 40–64, 65–84, and ≥85, respectively; in males a significant relationship was found between Romberg test and age groups (p = 0.002). There were 33, 48, and 7 females (n = 898) with abnormal neurological-Romberg tests for age groups 40–64, 65–84, and ≥85, respectively; in females a significant relationship was found between the Romberg test and age groups (p = 0.001).

There were 17, 10, and 5 males (n = 401) diagnosed for neurological-muscle strength abnormalities in age groups 40–64, 65–84, and ≥85, respectively; in males a significant relationship was found between muscle strength and age groups (p = 0.001). There were 37, 34, and 11 females (n = 903) diagnosed for neurological-muscle strength abnormalities in age groups 40–64, 65–84, and ≥85, respectively; in females a significant relationship was found between muscle strength and age groups (p = 0.001).

There were 20, 15, and 2 males (n = 399) diagnosed for diminished neurological-sensory intact (hands/feet) for age groups 40–64, 65–84, and ≥85, respectively; no significant relationship was found between sensory intact (hands/feet) and age groups (p = 0.76). There were 35, 30, and 3 females (n = 902) diagnosed for diminished neurological-sensory intact (hands/feet) for age groups 40–64, 65–84, and ≥85, respectively; a significant relationship was found between sensory intact (hands/feet) and age groups (p = 0.004).

Figure 2 is a visual representation of cognitive disorder differences in gender. It is evident that the development of dementia, age-associated cognitive impairment (AACI), cognitive impairment, no dementia (CIND), and mild cognitive impairment (MCI) is higher in males than females. Normal cognition level is higher in females than males by about 10%.

Fig.2

Comparison of cognitive disorder between males and females.

Table 2 shows the relationship between cognitive disorder and hypertension. Among the males with normal cognition levels (n = 303), there were 126 who did not have hypertension and 177 who had symptoms of hypertension. From the males with AACI (n = 31), there were 12 who did not have hypertension and 19 who did. Among the males with CIND (n = 17), there were 7 who did not have hypertension, and 10 who had symptoms of hypertension. For the males with MCI (n = 86), there were 18 who did not have hypertension and 68 who had symptoms of hypertension. For the males with dementia (n = 15), there were 4 who did not have hypertension and 11 who had symptoms of hypertension. There was a significant association between all cognitive disorders and hypertension for males (p = 0.011).

Table 2

Cognitive disorder and hypertension for males and females

	Hypertension
	Male				Female
Cognitive Disorder	No	Yes	Total	p	No	Yes	Total	p
Normal Cognition	126	177	303	0.003	400	396	796	0.890
AACI	12	19	31	0.210	16	32	48	0.020
CIND	7	10	17	0.470	12	18	30	0.270
MCI	18	68	86	0.001	36	118	154	0.001
Dementia	4	11	15	0.07	5	5	10	0.990
Total	167	285	452	0.001	469	569	1038	0.002

For the females with normal cognition levels (n = 796), there were 400 who did not have hypertension and 396 who had symptoms of hypertension. Among the females with AACI (n = 48), there were 16 who did not have hypertension and 32 who did. Among the females with CIND (n = 30), there were 12 who did not have hypertension, and 18 who had symptoms of hypertension. For the females with MCI (n = 154), there were 36 who did not have hypertension and 118 who had symptoms of hypertension. For the females with dementia (n = 10), there were 5 who did not have hypertension and 5 who had symptoms of hypertension. There was a significant association between all cognitive disorders and hypertension for females (p = 0.0001).

Hyperlipidemia is prevalent in individuals with hypertension [26], and 65% of males (n = 303) had hyperlipidemia, but the association between hyperlipidemia and hypertension was not significant (p = 0.14), OR: 1.35, 95% CI: (0.91, 1.99). Also, 55% of females (n = 618) had hyperlipidemia and the association between hyperlipidemia and hypertension was significant (p = 0.0001), OR: 1.76, 95% CI: (1.37, 2.26).

Hyperthyroidism is also prevalent in individuals with hypertension and causes the condition in 3% of patients [27]. In males, there was no significant association between hypertension and hypothyroidism (p = 0.25), OR: 1.39; 95% CI: (0.79, 2.26), but in females, there was a significant association (p = 0.003), OR: 1.57, 95% CI: (1.17, 2.12).

There was no significant relationship between hypertension and AD for either males (p = 0.46), OR: 1.31, 95% CI: (0.63, 2.69) or females (p = 0.37), OR: 1.20, 95% CI: (0.80, 1.79).

Table 3 reflects the relationship between hypertension and diabetes. In males (n = 461), 139 did not have hypertension or diabetes, 106 had both hypertension and diabetes, 181 had hypertension and did not have diabetes, and 35 did not have hypertension but did have diabetes. In males, there was a significant relationship between hypertension and diabetes (p = 0.001), OR: 2.33, 95% CI: (1.50, 3.62). In females (n = 1047), 402 did not have hypertension or diabetes, 195 had both hypertension and diabetes, 377 had hypertension and did not have diabetes, and 73 did not have hypertension but did have diabetes. In females, there was a significant relationship between diabetes and hypertension (p = 0.001), OR: 2.85, 95% CI: (2.10, 3.86).

Table 3

Diabetes and hypertension for males and females

	Hypertension
	Male				Female
	No	Yes	Total	p	No	Yes	Total	p
No Diabetes	139	181	320	0.020	402	377	779	0.370
Diabetes	35	106	141	0.001	73	195	268	0.001
Total	174	287	461	0.001	475	572	1047	0.002

Table 4 reflects the relationship between hypertension and CVD. In males (n = 461), 155 did not have hypertension or CVD, 41 had both hypertension and CVD, 246 had hypertension and did not have CVD, and 19 did not have hypertension but did have CVD. In males, there was no significant association between hypertension and CVD (p = 0.30), OR: 1.36, 95% CI: (0.76, 2.43). In females (n = 1047), 465 did not have hypertension or CVD, 68 had both hypertension and CVD, 504 had hypertension and did not have CVD, and 10 did not have hypertension but did have CVD. In females, a significant association was found between hypertension and CVD (p = 0.001), OR: 6.27, 95% CI: (3.19, 12.33).

Table 4

Cardiovascular disease (CVD) and hypertension for males and females

	Hypertension
	Male				Female
	No	Yes	Total	p	No	Yes	Total	p
No CVD	155	246	401	0.001	465	504	969	0.210
CVD	19	41	60	0.005	10	68	78	0.001
Total	174	287	461	0.001	475	572	1047	0.003

Table 5 shows the relationship between hypertension and depression. In males (n = 460), 147 did not have hypertension and depression, 61 had both hypertension and depression, 226 had hypertension and did not have depression, and 26 did not have hypertension but did have depression. In males, there was no significant association between hypertension and depression (p = 0.09), OR: 1.53, 95% CI: (0.92, 2.53). In females (n = 1046), 382 did not have hypertension and depression, 160 had both hypertension and depression, 412 had hypertension and did not have depression, and 92 did not have hypertension but did have depression. In females, there was a significant association between hypertension and depression (p = 0.001), OR: 1.61, 95% CI: (1.20, 2.16).

Table 5

Depression and hypertension for males and females

	Hypertension
	Male				Female
	No	Yes	Total	p	No	Yes	Total	p
No Depression	147	226	373	0.001	382	412	794	0.290
Depression	26	61	87	0.001	92	160	252	0.001
Total	173	287	460	0.001	474	572	1046	0.002

In Table 6, a study was done to assess the rate of hypertension between two ethnicities, Hispanics and non-Hispanics. We have computed a non-Hispanic group by merging non-Hispanic White, Black/African, and Other, and then performed statistical analysis. A total of 460 males and 1,045 females participated in the study. There was a higher rate of hypertension among male Hispanics with 150 males diagnosed with hypertension than male non-Hispanics in which 137 had hypertension. There was a higher rate of hypertension among 309 female Hispanics and 263 non-Hispanic females. There was a higher rate of hypertension among female Hispanics than male Hispanics. There was a higher rate of hypertension observed among non-Hispanic females than non-Hispanic males. There was no significant association between Hispanic and non-Hispanic males with hypertension (p = 0.08), OR: 1.41, 95% CI: (0.96, 2.07). In females, there was significant association between Hispanic and non-Hispanic with hypertension (p = 0.026), OR: 1.33, 95% CI: (1.03, 1.70).

Table 6

Ethnicity and hypertension for males and females

	Hypertension
	Male				Female
	No	Yes	Total	p	No	Yes	Total	p
Hispanic	105	150	255	0.005	288	309	597	0.390
Non-Hispanic	68	137	205	0.001	185	263	448	0.001
Total	173	287	460	0.001	473	572	1045	0.002

Table 7 shows the comparisons of AD between Hispanic and non-Hispanic ethnicities. In this study, 243 males and 561 females participated. There was a higher rate of AD among 25 non-Hispanic males compared to 16 males in the Hispanic ethnicity. Among females, a higher rate of AD was observed in the Hispanic ethnicity (n = 74) compared to 51 females who had the same disease within the non-Hispanic category. There was a higher rate of AD among females in the Hispanic ethnicity than males. A higher rate of AD was observed in non-Hispanic females than non-Hispanic males. In males, there was a significant association between ethnicity and AD (p = 0.0001), OR: 3.447, 95% CI: (1.721, 6.904). In females, there was a significant association between ethnicity and AD (p = 0.045), OR: 1.520, 95% CI: (1.009, 2.291).

Table 7

Ethnicity and Alzheimer’s disease for males and females

	Alzheimer’s disease
	Male				Female
	No	Yes	Total	p	No	Yes	Total	p
Hispanic	139	16	155	0.001	300	74	374	0.001
Non-Hispanic	63	25	88	0.001	136	51	187	0.001
Total	202	41	243	0.001	436	125	561	0.001

Figure 3 divides the patient demographic for hypertension by race and ethnicity where the sample was predominantly Hispanic. It displays male and female participants that were Hispanic, Non-Hispanic White, Black African American, and Other. All males have less hypertension when compared to female participants. Additionally, female participants that were Hispanic and Non-Hispanic White had a higher rate of hypertension compared to males.

Fig.3

Race/ethnicity and hypertension for males and females.

Figure 4 depicts AD for race and ethnicity of male and female participants. Among Hispanic and non-Hispanic whites, there was a lower chance of AD in Hispanic males compared to females and a lower chance in non-Hispanic White males compared to non-Hispanic White females.

Fig.4

Race/ethnicity and Alzheimer’s disease for males and females.

Figure 5 exhibits cognitive disorder among the MCI male and female participants. Non-amnestic single domain, amnestic single domain, non-amnestic multiple domain, and amnestic multiple domain are higher in females than males. For males, the highest number of patients were found in amnestic single domain and for females it was amnestic multiple domain. On the other hand, the least number of patients were classified as non-amnestic multiple domain for both males and females.

Fig.5

Cognitive disorder with MCI classification for males and females.

DISCUSSION AND FUTURE DIRECTIONS

Chronic diseases such as dementia and hypertension place a tremendous burden on the healthcare system [7, 14]. The results obtained from the participants in the Project FRONTIER database shows no significant association between hypertension and dementia for both males and females. Similarly, there was no significant association between AD and age or dementia and age in the groups assessed. However, there was in fact a borderline relationship between neurological stroke and age for males and a significant relationship for females. Other neurological variables were also assessed, and factors like parkinsonism, reflexes, and sensory intact showed a significant association with age in females. A statistically significant association was found when comparing the age groups to hypertension for both males and females. We found significant relationships between cognitive disorders and hypertension for both males and females. A significant relationship between hyperlipidemia and hypertension in female participants was also found. Furthermore, we assessed the relationship between hypertension and other risk factors like diabetes, CVD, and depression. Diabetes was significantly associated with hypertension in both males and females. For both CVD and depression, there was a significant association with hypertension in the case of females, but not males.

A number of results in this study were similar to those found in the current literature. Diabetes was found to be significantly associated with the development of dementia in both males and females [8, 9], which was consistent with our findings. Diabetes and risk of hypertension were significant for both genders and confirm with the literature [18]. However, unlike published works, CVD and depression were found to be significantly associated with dementia in females only rather than in both genders [10, 11].

Also, a significant association between hypertension and cognitive disorder was discovered for both genders, but no significant association was found between hypertension and dementia for either gender. The current literature, however, has yielded mixed results for the association between hypertension and cognitive disorder and dementia. A few studies have found hypertension and dementia to be statistically significantly associated while others have not [17 , 21]. This indicates the need for further research in rural counties to investigate the aforesaid relationships. Finally, other studies found a significant association between hypertension and diseases such as depression and CVD for both genders [18]. This study, however, has only found a statistically significant relationship between hypertension and these diseases in females only.

Male and female Hispanics and non-Hispanics were significantly associated with AD, and both Hispanic and non-Hispanic females were significantly related with hypertension. Overall, the findings of this study are novel in addressing dementia and hypertension incidence in rural West Texans.

It is worth noting that many other risk factors exist for both dementia and hypertension and the hope is to explore them in future studies on the basis of availability of data. Additionally, Project FRONTIER is still collecting dementia-related disease data from four rural West Texas counties. Incorporating related data with appropriate sample size from those risk variables will assist in finding more significant risk variables to generalize the findings for race/ethnic similarities and other geographically similar counties and will be helpful in measuring the future progression of the disease. It is worth noting that minority populations and people who live in rural and underserved areas tend to not have access to proper healthcare facilities. These economically disadvantaged individuals lack health insurance and often do not receive adequate care for their diagnosis, which can delay their prognosis and lengthen their recovery time. It is important to improve the treatment options for those individuals and modify the existing policies to ensure more comprehensive diagnosis coverage and better quality of life for these people. The findings of this study may guide relevant policymaking to reduce dementia incidence as well as other chronic diseases in rural West Texans.

Limitations of the study

There were several limitations in this study. First, data was based on prevalent cases identified in a hospital setting. Second, the data did not include information about who died from dementia. Third, there was no longitudinal data collected from participants and no report on how this may have resulted in lower risk factor levels with a number of follow-ups. Fourth, there was no record found as to the appropriateness of treatment and follow-up. Fifth, while collecting data for some questions, there were a small number of responses that made running a statistical chi-squared test problematic. Sixth, data was available only for limited variables on chronic diseases and Project FRONTIER is still continuing to collect information from rural West Texas participants.

Footnotes

ACKNOWLEDGMENTS

The authors would like to thank Texas Tech University Health Sciences Center for approving the IRB application and allowing their support to access the database on rural West Texas counties and also providing relevant information which improved the statistical data analysis presentation of the findings. Currently, the Garrison Institute on Aging (GIA) research and outreach programs are supported by the Garrison Family Foundation, NIH grants AG042178, AG047812, and the Texas Department of State Health Services and the Corporation for National and Community Service. The authors sincerely thank the residents of Lubbock Community Centers, who participated in the study.

Authors’ disclosures available online ().

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