Vitamin D deficiency increases risk of type 2 diabetes for patients with HIV

Vitamin D deficiency is associated with an increased risk of type 2 diabetes for patients with HIV, Italian investigators report in the online edition of AIDS.

The study also showed that almost two-thirds of HIV-positive patients had inadequate levels of vitamin D.

“Studies should examine whether vitamin D supplementation can prevent or treat type 2 diabetes mellitus in HIV and possibly reduce complications associated with HIV infection and its treatment,” recommend the researchers.

Thanks to antiretroviral therapy many patients with HIV are living longer and healthier lives. However, some anti-HIV drugs can cause metabolic problems that can lead to the development of type 2 diabetes.

In addition, several studies have also shown that many patients with HIV have low levels of vitamin D, and research involving HIV-negative individuals has demonstrated that insufficient amounts of this vitamin can increases the risk of diabetes.

Investigators from the Modena HIV Metabolic Clinic Cohort wished to see how many of their patients had vitamin D deficiency (below 20 ng/dl) and if patients with vitamin D deficiency were more likely to have type 2 diabetes than those with adequate levels of the vitamin.

They therefore conducted a prospective cross sectional study involving 1811 patients who received care between 2005 and 2008.

Individuals were defined as having type 2 diabetes if their fasting glucose level was at least 126 mg/dl; if their doctor had diagnosed them with type 2 diabetes; or if they were taking medication for the condition.

Analyses were also conducted to see if low levels of vitamin D increased the risk of metabolic syndrome.

Mean vitamin D levels were 19 ng/dl, and 64% of patients had deficient levels of the vitamin.

A total of 116 patients had type 2 diabetes, and vitamin levels were significantly lower in these patients than other individuals (15 vs. 19 ng/dl, p < 0.001).

After adjusting for factors that can increase the risk of diabetes (age, sex, body mass index and co-infection with hepatitis C), the investigators found that vitamin D deficiency was significantly associated with an increased risk of type 2 diabetes (adjusted odds ratio [OR] = 1.85; 95% confidence interval [CI], 1.03-3.32, p = 0.038).

There was also a relationship of borderline significance between vitamin D deficiency and metabolic syndrome (OR = 1.32; 95% CI, 1.00-1.75, p = 0.053).

“Our study identified a high prevalence of vitamin D deficiency among HIV-infected patients,” comment the researchers, “patients with type 2 diabetes…had lower vitamin D levels compared with individuals without type 2 diabetes, although both groups met criteria for vitamin D deficiency.”

The investigators note “the findings of our study are consistent with those of HIV-uninfected individuals and suggest that the association between vitamin D deficiency and type 2 diabetes mellitus is also present among HIV-infected individuals.”