In this study, male PWLH were on a combination of non-nucleoside reverse transcriptase inhibitors (NNRTIs) and two nucleoside analogues (NRTI) which were preferred treatment ART modalities for their unique antiviral activity, high specificity, and low toxicity²³. In this study male PLWH on CART for more than 10 years featured abdominal obesity as demonstrated by higher mean values of waist circumference, waist-to-hip ratio and supra-iliac skinfold thickness at the end of study period. Furthermore, increased truncal and peripheral adiposity in arms and legs was also observed in this group. As for lipid markers, the mean values of LDL cholesterol and total cholesterol were significantly higher than the baseline mean values. This can be attributed to the cumulative exposure to NNRTIs and NRTI for a long duration probably causing hypercholesterolaemia as evidenced in a study on 1664 individuals with HIV including Caucasians, Black Africans and other ethnic groups²⁴. An observational cohort study from Poland, evaluated the changes in lipid profile of 70 PLWH (males n = 58 females; n = 12) before implementation of ART and after 1 year of continuous ART. At the end of the first year of ART, significant increases in total cholesterol, LDL cholesterol, HDL cholesterol, and non-HDL cholesterol levels were observed when compared to the baseline lipid profile²⁵.However, this study did not evaluate for changes in measures of body composition or insulin resistance.

A meta-analysis of observational and interventional studies with comparable ART-treated and ART-naïve populations from sub-Saharan Africa demonstrated ART associated elevated total cholesterol, triglycerides, LDL-cholesterol, and lower HDL cholesterol cumulatively leading to increased cardiovascular risk. However, no significant association was observed between ART and risk of hypertension and diabetes in PWLH from the Sub-Saharan region²⁶.

Altered fat repartition, diagnosed as lipodystrophy, has been related to first-generation nucleoside-reverse-transcriptase-inhibitors (NRTIs) (Stavudine and Zidovudine) and some protease inhibitors⁸.Fat deficiency in lipodystrophy leads to a combination of metabolic disturbances including insulin resistance, hypertriglyceridemia, and ectopic fat accumulation²⁷ eventually resulting in increased risk of cardiovascular diseases in HIV patients on CART. Globally, this burden is anticipated to increase, given the rapid scale-up of ART regimens and increasing lifespan of HIV-infected patients on long-term ART therapy²⁸.

Lipodystrophy can manifest as two distinct phenotypes: fat accumulation (lipo-hypertrophy) or fat loss (lipoatrophy). Lipo-hypertrophy occurs in the truncal areas and manifests as abdominal obesity, mammary hypertrophy, accumulation of fat on the neck, or lipomas. In contrast, lipoatrophy occurs on the face, gluteal regions, arms, and legs. In some patients, both these manifestations may coexist²⁹. The clinical lipoatrophy syndrome in CART-treated patients emanates from specific adipocyte and stromal vascular cell damage³⁰ and differs significantly from the “wasting syndrome” The wasting syndrome primarily arises from a profound caloric deficit causing loss of muscle mass instead of fat^23,29.

Globally, the age-standardised total prevalence of diabetes was higher in males (6.5%) when compared to females (5.8%) between the years 1990 to 2021¹². Amongst Asian Indians males aged between 45 years to 49 years, the prevalence of diabetes in India increased from 8.8% in the year 1990 to 11.1% in the year 2016³¹.

A previous cohort study from the same institution had demonstrated a high prevalence of cardiometabolic risk markers in urban and rural cohorts of the general population. Specifically, in individuals aged between 29 and 42 years, the prevalence of overweight/obesity increased from 17 to 51%; that of type 2 diabetes from 3 to 16%; that of hypertension from 2 to 20% and that of hypertriglyceridemia from 16 to 30%³².

A previous study in HIV patients on ART for 12 months (n = 30) and ART naive HIV patients (n = 30), reported the incidence of diabetes in HIV patients on ART as 20%³³. In comparison to the former study³³, the incidence of diabetes in PLWH aged above 45 years had increased from 10.3% at baseline to 20.6% at the endpoint as shown in this study. Notably, islet cell autoimmunity or beta cell destruction has not been evidenced in HIV patients³⁴.

Insulin resistance in PLWH on CART has been studied in other populations. A cross-sectional study by Freitas and colleagues from Portugal, compared 217 clinically stable HIV-infected male and female patients receiving cART for 3 years against 74 BMI matched controls. It was noted that HIV-infected patients had significantly higher waist/hip ratio, fasting glucose, triglyceride, insulin and HOMA-IR indicative of dysglycemia³⁵. A study by Bigolonia and colleagues in PLWH (n = 39) on CART for three years demonstrated a consistent increase in insulin resistance and a concomitant decrease in insulin secretion. All patients had impaired fasting glucose at baseline, which worsened during the course of ART, irrespective of the type of ART regimen³⁶.

In a multiethnic study involving 327 HIV-infected and 3240 HIV-uninfected subjects aged between 35 and 70 years, reported that nucleoside and non-nucleoside reverse transcriptase inhibitor therapy were associated with a higher risk of diabetes in PLWH. HIV infection by itself was not the risk factor for diabetes, but the cumulative effect of increasing age, BMI and continued CART, leading to the differential level of immune activation and inflammatory response in HIV infected when compared to uninfected persons³⁷.Weight gain is common in PLWH on ART and may be attributed to a reduction in inflammation-related catabolism³⁸, the composition of ART regimen and demographic factors³⁹. In this study, the mean values of total body mass, waist circumference, waist-to-hip ratio, truncal fat mass, and fat in upper limbs and total fat mass were significantly higher when compared to baseline values. This phenotype predisposes to insulin resistance which is evident with the mean value of the Mcauley index (a surrogate index of insulin sensitivity) being significantly lower at end of study period. A large study of 22,972 male PLWH on ART including NNRTI, PI and INSTI reported 10 times higher odds for weight gain in individuals aged above 33 years. It was reported that after three years of ART, 32% of normal‐BMI PLWH initiated on an INSTI‐based regimen had become overweight, compared to 29% of those on a PI‐based regimen and 25% on a NNRTI‐based regimen⁴⁰. A pooled analysis of eight randomised controlled trials comprising of more than 5000 treatment-naive PLWH initiated on ART demonstrated weight gain was significant in PWLH on newer ART regimens. Specifically, integrase strand transfer inhibitor based ART regimen was associated with more weight gain when compared to protease inhibitors or nonnucleoside reverse transcriptase inhibitors (NNRTIs) based ART regimen⁴¹.

Lipoatrophy, characterized by fat loss is often associated with higher cumulative exposure to NRTIs, particularly Stavudine²⁸. In this study, the male PLWH were on Zidovudine, Lamivudine, Nevirapine and Stavudine as the first-line ART as practised in most low and middle income countries⁴². However, we observed no significant changes for BMI in PWLH on ART for less than or more than ten years, whereas the mean waist circumference had significantly increased in PLWH on ART for more than 10 years. This was concomitant with significant increases in truncal fat mass, fat mass in right and left legs, total fat mass and a significant decrease in insulin sensitivity in the same group. On pooled analysis, a significant increase in fat mass, truncal fat mass, fat mass in upper limbs, waist and hip circumferences and waist-to-hip ratio were observed at end of study period, when compared to baseline values. However, significantly lower mid-arm circumference, triceps skinfold thickness and fat percentage in lower limbs were observed in PLWH on ART when compared with healthy individuals. This could be due to loss of muscle mass in the arms and the cumulative effect of fat loss in the legs due to prolonged CART regimen in male PLWH.

In this study, the treatment regimen comprised of a combination of two nucleoside analogues (NRTI) and a non-nucleoside reverse transcriptase inhibitor (NNRTI). The mean serum testosterone level at end of study period was significantly lower (29%) when compared to the baseline values. In PLWH on ART for more than 10 years, the mean decrease in testosterone levels was 31.4%, while in PLWH on ART for less than 10 years, the mean decrease in testosterone levels was 30%. The mean value of serum testosterone in PWLH on ART for a duration less than or greater than 10 years was higher than 300 ng/dl when compared to the former. However, in the current study hypogonadism (serum testosterone < 300 ng/dl) was noted only in 4 (13.7%) patients. A recent meta-analysis has reported that the prevalence rate of acquired hypogonadism in male PWLH was 26%⁴³. A study on Indian MLWH (n = 225; aged between 18 and 70 years) and on highly active ART for a duration of 8 years reported a prevalence rate of 39% of hypogonadism (serum testosterone < 300 ng/dl)⁴⁴. The SWISS cohort study in 139 Caucasian male PLWH treated on zidovudine/lamivudine-based CART for two years reported secondary hypogonadism even at low or normal luteinising hormone levels⁴⁵. The interpretation of the results of testosterone assays is more difficult in men with HIV due to several confounding factors such as increasing age, lower baseline CD4 count and lower Vitamin D levels in PLWH on ART⁴⁶.

To sum up, in this cross-sectional, observational study, male PLWH on CART for more than a decade featured increased body weight, higher body fat percentage, total body fat mass, higher abdominal adiposity as shown by higher truncal fat percentage, waist circumference and triceps skinfold. In addition, increased fat mass in upper limbs alongside, reduced beta cell function, impaired glucose tolerance, insulin resistance and lower testosterone levels were also observed when compared to baseline.

Considering the alteration in body habitus and onset of insulin resistance and lipodystrophy that may occur in PLWH on CART, early diagnosis of the same set of patients with appropriate substitution of ART including new generation ART drugs may be advocated. Furthermore, early detection of insulin resistance and prediabetes in such patients are likely to help in ART regimen adjustments to minimize the metabolic adverse effects. The management strategies for diabetes and dyslipidaemia in PLWH will differ when compared to the general population and thereby requires a cautious choice of pharmacotherapy. PLWH and pre-existing diabetes require clinical counselling about the possible alterations in metabolic function, and the chances of drug interactions between oral antidiabetic drugs and ART. PLWH who are detected to have diabetes at onset of therapy or later, may benefit from insulin as it is safe and effective⁴⁷. The results of this cross-sectional study are intended to provide the impetus for prospective, randomised controlled studies of the interactions among drug and host factors in the development of fat distribution abnormalities in PLWH.

The merits of the study include detailed body composition assessment, biochemical analysis, and assessment of insulin resistance in a demographically homogenous cohort of male PWLH on CART who were followed-up after 10 years at a single centre. This excludes the effects of gender on the phenotype and body composition, unlike other studies which include male and female patients with HIV. Secondly, this study provides data on the longitudinal phenotype changes in male PWLH who were on a combination of two nucleoside analogues (NRTI) and a non-nucleoside reverse transcriptase inhibitor (NNRTI) ART, unlike others studies which reported data on CART inclusive of protease inhibitors.

The limitations of the study are acknowledged. This study included a relatively small sample size of Asian Indian males with HIV at baseline and the same cohort was followed up after 10 years. Therefore, hence the results are applicable only to Asian Indian males. Subsequent studies should include female PWLH to explore potential gender specific differences in phenotypic and metabolic outcome due to CART. The healthy, non-HIV males (controls) recruited at baseline were not followed-up till the end of study, therefore longitudinal data of the control group was not available for comparisons. As quantitative data of diet and physical activity was not obtained at baseline and the end of the study, therefore the confounding effects of these factors, if any could not be studied. Furthermore, this is an observational study and therefore the cause and effect of metabolic changes in PLWH on ART cannot be definitively ascertained.

It is important to mention that the HIV viral load testing facility was not available at the institution during the study period and therefore it was not analysed for all PWLH. As of the year 2017, most of the study patients were part of the National AIDS Control Programme sponsored by the Government of India, and antiretroviral therapies were provided free of cost along with CD4 testing. In cognizance of the same, the government of India declared HIV viral load testing a standard diagnostic criterion for all PWLH in the year 2017. This was in accordance to the National “Test and Treat” policy launched on April 28, 2017. The National AIDS Control Organization (NACO) in India has formulated policies to adhere to the global targets of ending HIV in India, and to reduce the new infections annually and the mortality rate by 80% by the year 2025–2026. It is envisaged to achieve this by promoting universal access to viral load testing facilities to people in need of ART as mentioned in the report of the National Aids Control Organisation (NACO) for the year 2021. Subsequently, in the year 2024, there were 64 public-sector viral testing laboratories operating under the National AIDS Control Program in India⁴⁸. As of today, HIV viral load testing is a standard protocol at the study centre and is applied in all studies in PLWH.

(a): Mixed model analysis showing differences in HOMA-IR between groups. (b) : Mixed model analysis showing differences in HOMA beta between groups. (c): Mixed model analysis showing differences in QUICKI between groups. (d) : Mixed model analysis showing differences in McAuley index between groups.