Eating Habits and Possible Effects of Mediterranean Diet on Body Composition in Ageing People Living with HIV in Two Italian Centres

Background: The relationship between diet and body composition in people with HIV (PWH) is still not well defined. Therefore, our primary objective was to assess the association between Mediterranean diet (MD) adherence and body composition measured by whole-body dual-energy X-ray absorptiometry (DXA). Secondly, we aimed to assess differences between people living in the north (Padua, Veneto Region, Italy) vs. those living in the south of Italy (Catanzaro, Calabria Region, Italy) and with respect to ethnicity. Methods: In this cross-sectional study, adults with HIV with a confirmed virological suppression were enrolled at two Italian HIV clinics. MD adherence was assessed using the validated MedDiet Score, with high adherence being defined as a score ≥ 25. All participants underwent whole-body DXA. Anthropometric and DXA-derived measures were compared between people with high vs. low adherence to MD, and multivariable linear regression adjusted for age, sex, and CD4+ count at nadir was performed. Results: Among 130 participants (81.5% male; median age 57 years), 105 (80.8%) showed high MD adherence. High adherence to MD was more common among participants from Southern Italy than among those from Northern Italy and was associated with Caucasian ethnicity, higher education, higher CD4+ count and CD4/CD8 ratio, and a lower prevalence of obesity and neurological disorders. DXA analyses showed lower total and trunk fat mass and higher lumbar spine bone mineral density in highly adherent individuals. After adjustment, high MD adherence remained independently associated with lower BMI (β −5.3, 95% CI −7.3 to −3.4; p < 0.001). Conclusions: In ageing PWH, high MD adherence was associated with a more favourable clinical profile and healthier body composition, particularly lower central adiposity and BMI. Prospective and interventional studies are needed to clarify the role of this type of diet in PWH.