The study has demonstrated a high prevalence of dyslipidaemia (70.2%) in HIV-patients receiving first-line ART in a predominantly rural population of Cameroon. Hypertriglyceridaemia (51.8%), raised levels of LDL-c (33.3%) and hypercholesterolaemia (29.8%) were the most common forms of dyslipidaemia. The duration on ART, smoking, alcohol use and the presence of a concurrent metabolic disease were significantly associated with high LDL-c values. LDL-cholesterol is a pro-atherogenic marker.
Though high, the prevalence of dyslipidaemia in our setting is lower to the reported rate of 82.3% in patients using ART in an urban population of Southern Ethiopia
 and to that observed in Dar es Salaam, Tanzania where the prevalence was 76% in ART-naive patients
 but much more higher than prevalence rates observed in the developed world
. The prevalence rates of hypertriglyceridaemia and high LDL-c levels in our study were comparable to those observed in Southern Ethiopian study (55.8% and 33.6% respectively)
 but were respectively higher (43.5%) and lower (46.4%) in the urban Cameroon setting
. The prevalence rates of hypercholesterolaemia and low HDL-c concentration in our study were lower than those reported in these studies. In the general population of Cameroon, dyslipidaemia was observed to be more prevalent in the urban than in the rural setting
. It is however difficult to ascertain whether the prevalence and pattern of dyslipidaemia in HIV-infected population in rural area is different from that in an urban settings because dyslipidaemia in HIV-infected individuals is a complex condition, with multiple contributing factors including the HIV virus itself, individual genetic characteristics and antiretroviral therapy-induced metabolic changes
Women were associated with a greater risk of lipid disturbances than men though our study lacked the evidence to support this association. Increasing the power of our study and adjusting for body mass index could have improved our probability of detecting the sex difference. However, this finding is coherent with current knowledge that women experience more ART-induced (metabolic) adverse effects than men
As age increases, pro-atherogenic lipid parameters also increase
. In our study, though it appeared that younger persons below the age of 25 years were at lower risk of dyslipidaemia, there was no pattern for the association between age and abnormal lipid profile. Poor categorisation of age groups in our study might have been responsible for the inability to detect any significant relationship.
Severe immune suppression (low CD4 count) has been associated with dyslipidaemia in ART-naive HIV infected persons
[19, 22, 23]. However, in a cohort of persons doing well on highly active antiretroviral therapy (HAART) with a sufficiently improved mean CD4 count, there is little variability in CD4 count of the group and therefore a difference in dyslipidaemia cannot be attributed to differences in CD4 counts. The latter is the case in our study and in other studies involving patients on HAART
HAART is associated with a cardio-protective lipid profile in the short term
 because after initiation of ART, lipid levels return to baseline levels but soon they rise above pre-sero-conversion levels in the long term
. In our cohort, patients with duration on ART above two years were significantly associated with a poor lipid profile. It might be therefore reasonable to recommend that monitoring of lipid profile should be instituted after two years on first line ART in Cameroon. Current guidelines of The National AIDS Control Committee of Cameroon do not allow for routine monitoring of lipid parameters for patients receiving first line ART
. Though an earlier study in Cameroon by Yone et al. did recommend monitoring of lipid profile in patients on first line ART, the timing for this laboratory assessment was not mentioned.
Stavudine is known to be associated with a significant increase in lipid parameters compared with either zidovudine
[27, 28] or tenofovir
. Our data suggested a similar comparison. Following the 2010 WHO Guidelines
, most patients on stavudine had already been switched to either zidovudine or tenofovir at the time of the study. The effect of this intra- class switching has not been accounted for but the likely impact on the odd ratios would be a bias towards unity because the switching was independent of this study.
A head-to-head comparison of efavirenz with nevirapine in initial regimens demonstrated a more favourable lipid profile for nevirapine at 48 weeks
. Our data showed the contrary and the likely explanation is that, in our cohort, regimens were selectively prescribed to certain groups of patients according to their immune status or the presence of tuberculosis or pregnancy. This selection bias could account for the difference observed.
A comprehensive meta-analysis by Craig et al. has demonstrated that compared with non-smokers, cigarettes smokers had poorer lipid profiles both in the general population
 and even amongst the HIV-positive population
. Though the proportion of current smokers in our sample population was very small and made up exclusively of men, the association is in agreement with current knowledge and in this study smokers even had the highest odds of dyslipidaemia than any other subgroup. Information bias associated with under-reporting of undesirable lifestyles is likely to be the case here but such a big odd ratio is also unlikely to be a chance finding. Smoking cessation would thus be strongly recommended.
The proportion of alcohol users in our study sample was high just like in the general Cameroon population. Our data suggest that alcohol consumers have better lipid profiles than non-drinkers. It is however not known what unit of daily intake was associated with a favourable lipid profile because we could not determine the quantity consumed per participant. With women in a rural African setting making up the majority of our study population, it is plausible that users of alcohol would be mostly low-to-moderate drinkers. Alcohol consumption should however be discouraged because its deleterious effects on ART adherence and HIV progression
 and on other cardiac-metabolic disorders
 do outweigh this supposedly positive effect on lipid parameters. Incidentally, patients with existing metabolic disorders (all of whom were sufferers of type 2 diabetes mellitus) have been shown to have very high odds of dyslipidaemia (LDL-c) in this study.
Our study had a couple of draw-backs that may impact on its quality. The sample size was small so much so that the precision of our odd ratios was low and we lacked the power to detect significant differences we hoped to. Its opportunistic nature had somehow introduced selection bias because patients turning up for their routine check-up might be different from those defaulting. The cross-sectional design made it impossible to assume any causality.