Abstract
Antiretroviral (ARV) therapy in HIV patients can cause hyperlipidaemia, glucose intolerance and insulin resistance, which increase the risk of cardiovascular disease (CVD). An audit carried out in Manchester found that CVD risk factors were common among HIV patients receiving ARVs; however, the management of risk factors was not satisfactory. Adopting a formal system to identify and manage CVD risk factors as well as appropriate referral for specialist management of complications of ARV therapy would improve patient care.
INTRODUCTION
Antiretroviral treatment (ART) has reduced the morbidity and mortality of HIV disease. These drugs can cause hyperlipidaemia, glucose intolerance and insulin resistance, which increase the risk of cardiovascular disease (CVD). 1,2 It is therefore important to identify and appropriately treat risk factors for CVD in HIV patients.
We performed an audit of CVD risk management by HIV units in Greater Manchester. The standard was the Joint British Societies (JBS2) guidelines on prevention of CVD (December 2005).
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The JBS2 target population is individuals with
established atherosclerotic disease a risk of CVD ≥20% over 10 years diabetes mellitus (types 1 and 2) significant single risk factors:
systolic blood pressure (BP) ≥160 mmHg or diastolic BP ≥100 elevated total cholesterol:high-density cholesterol (TC:HDL-C) ratio ≥6 familial dyslipidaemia or a family history (FH) of premature CVD.
Interventions include lifestyle advice (smoking cessation, dietary, weight reduction, exercise). Aspirin, antihypertensives, statins and hypoglycaemic agents should be prescribed when indicated.
METHODS
We examined the case-notes of 78 patients under the care of 16 HIV consultants working within five clinics in Manchester. These clinics were of either infectious diseases or genitourinary medicine, and in total they had just over 2500 HIV patients registered for care. Data recorded between April 2005 and April 2006 were transferred to a standard proforma.
RESULTS
Three out of the five units self-reported that they followed the JBS guidelines. The mean age of patients was 39.5 years (range 24–70). Men comprised 69%; 58% were white and 33% were black African. Ethnicity was unrecorded in 6%. Forty-six percent of patients were smokers. Eighteen percent had a history of CVD (hypertension, ischaemic heart disease, cerebrovascular accident, diabetes or dyslipidaemia). Nineteen percent had an FH of premature CVD. Eight percent were hyperglycaemic and 8% had impaired glucose tolerance. CVD risk factors were not documented in a proportion of case-notes as follows: smoking status (19%), FH of CVD (40%) and previous CVD (17%). Table 1 shows BP and cholesterol levels. Forty-four percent of patients had high cholesterol (>5 mmol/L, the JBS2 audit standard). In all, 11.5% (9/78) had a systolic BP of ≥150 mmHg while 14.1% (11/78) had a diastolic BP of ≥90 (JBS2 audit standard BP <150/90). Five percent (4/78) had a calculated cardiovascular (CV) risk of ≥20%; 71.8% (56/78) had a CV risk of ≤20%, and a proportion of these (up to 36%) had one or more isolated risk factors (smoking, previous history of CVD or dyslipidaemia). In 21.8% (17/78), the CV risk could not be calculated due to incomplete data.
Blood pressure (BP) and cholesterol levels
Most patients were treatment experienced. The nucleoside/nucleotide reverse transcriptase inhibitor (NRTI) backbones used were tenofovir/emtricitabine (23%), zidovudine/lamivudine (20%), abacavir/lamivudine (19%) and other combinations (37%). Thirty-seven percent were on boosted protease inhibitor (lopinavir 17%, atazanavir 10%, fosamprenavir 6%, other 4%). Sixty-three percent were on non-NRTIs (efavirenz 42%, nevirapine 21%). Mean duration on treatment was 17months (range 0–72).
Units not following the JBS2 guidelines instituted corrective measures in nearly all patients with identified risk factors (5/5 smokers, 4/4 hypertensive patients, 5/6 dyslipidaemic patients and 4/4 overweight patients). Measures included counselling, referral, medication, advice or change of highly active antiretroviral therapy. Table 2 shows the management of patients in units that followed JBS2 guidelines.
JBS guidelines used
DISCUSSION
CVD risk factors are common in HIV patients on ART in Greater Manchester. Only approximately 5% of patients had a calculated CV risk >20%, but a proportion of notes (21.8%) data was incomplete to calculate the CV risk; therefore, this could be higher.
Measures to address risk factors, including drug treatment, were used regardless of whether JBS guidelines were used or not. Smoking and hyperlipidaemia were, in general, addressed while BP and glucose derangements were mostly not.
HIV units would improve patient care by the following methods:
Adopting a formal system to identify and manage CVD risk factors. Formal guidelines that are used in the general population and can equally apply to HIV patients include the JBS ones that we used as our standards in this audit; the World Health Organization guidelines for prevention of CVD, which take into account geographical diversity in the level of CVD risk;
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and the National Cholesterol Education Program guidelines for management of high cholesterol and CVD (Adult Treatment Panel III).
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Developing proformas to aid the recording of CVD risk factors and action taken. These could be used at the start of ART and revisited at regular intervals such as annually and filed in a patient's case-notes. Establishing clear referral routes (dietician, lipid or cardiology clinics, general practitioner, lipodystrophy clinic) for further specialist management.
Footnotes
ACKNOWLEDGEMENTS
We thank all the participating consultants: Dr E Wilkins, Dr G Alverez, Dr A Bonington, Dr A Ustianowski, Dr A Komolafe (North Manchester General Hospital); Dr V Lee, Dr A Sukthankar, Dr M Kingstone, Dr Orla McQuillan (Manchester Royal Infirmary); Dr Goorney (Hope Hospital); Dr E Morgan (Bolton Hospital); Dr Ahmed (Oldham Hospital); Dr H Lacey (Bailey Street Health Centre). We also thank the Audit Department at North Manchester General Hospital for providing the technical support and data analysis. Gilead Sciences funded the research post for the main author at North Manchester General Hospital Infectious Diseases Department.