Analysis of a large cohort of HIV-positive and negative veterans linked statin use to about a 40% lower risk of any cancer . The association held for both AIDS cancers and non-AIDS cancers.
Abundant research in the general population and in people with HIV suggests a link between statin use and lower cancer risk. But Veterans Affairs Cohort Study (VACS) researchers who conducted the new study noted that most previous work had small study groups and too little follow-up to clearly assess statin impact on new malignancies. Nor did these studies compare statin use in HIV-positive people and similar HIV-negative people.
The investigators determined 2000-2012 statin use in HIV-positive and negative VACS members. In statin users the study start date matched the first statin prescription; in nonusers the start date was a random visit date in the same year as the matched user. The VACS team matched each statin user to one nonuser by propensity score, which accounts for factors that might affect getting a statin prescription (age, year, smoking, chronic diseases, and lab values). They used Cox proportional hazards regression models to determine hazard ratios estimating statin impact on cancer incidence and mortality.
The analysis focused on 12,041 statin users matched to 12,041 nonusers. Almost all participants, 97%, were men, and 5015 had HIV infection. During 5.0 years of follow-up in statin users and 3.8 years in nonusers, cancer developed in 9.0% of veterans with HIV and 7.1% of HIV-negative veterans. Statin use cut the risk of any cancer, AIDS cancers, non-AIDS cancers, virus-related cancers, and virus-unrelated cancers in these HIV-positive and negative veterans, as indicated by the following hazard ratios (HR) (and 95% confidence intervals). For AIDS cancers and virus-related cancers the 95% confidence interval for veterans with HIV crossed 1.0.
-- All participants: HR 0.61 (0.56 to 0.67)
-- HIV-negative participants: HR 0.65 (0.59 to 0.72)
-- HIV-positive participants: HR 0.51 (0.40 to 0.64)
-- All participants: HR 0.31 (0.18 to 0.53)
-- HIV-negative participants: HR 0.39 (0.16 to 0.95)
-- HIV-positive participants: HR 0.28 (0.06 to 1.29)
-- All participants: HR 0.63 (0.58 to 0.69)
-- HIV-negative participants: HR 0.67 (0.60 to 0.74)
-- HIV-positive participants: HR 0.53 (0.41 to 0.67)
All virus-related cancers:
-- All participants: HR 0.64 (0.50 to 0.82)
-- HIV-negative participants: HR 0.59 (0.41 to 0.84)
-- HIV-positive participants: HR 0.57 (0.27 to 1.19)
All non-virus-related cancers:
-- All participants: HR 0.63 (0.57 to 0.70)
-- HIV-negative participants: HR 0.67 (0.60 to 0.75)
-- HIV-positive participants: HR 0.53 (0.39 to 0.70)
Statin use cut overall mortality by 45% (HR 0.55, 95% CI 0.50 to 0.62).
The VACS team concluded that "statin exposure is associated with lower risk of cancer independent of HIV status." They observed that the protective effect of statins appears greater for some virus-related cancers, which may reflect combined statin effects on tumor and viral pathogenesis.
1. Bedimo R, Shebl F, Sigel KM, et al. Statin exposure is associated with decreased risk of cancer. 25th Conference on Retroviruses and Opportunistic Infections (CROI). March 4-7, 2018. Boston. Abstract 132.