Systematic review and meta-analysis of the associations between body mass index, prostate cancer, advanced prostate cancer, and prostate-specific antigen

Sean Harrison,J L H Ruud Bosch,J Athene Lane,Kate Tilling,David E Neal,Hayley E Jones,Jenny L Donovan,Emma L Turner,Rosie Lennon,Freddie C Hamdy,Richard M Martin

doi:10.1007/s10552-020-01291-3

Abstract

PurposeThe relationship between body mass index (BMI) and prostate cancer remains unclear. However, there is an inverse association between BMI and prostate-specific antigen (PSA), used for prostate cancer screening. We conducted this review to estimate the associations between BMI and (1) prostate cancer, (2) advanced prostate cancer, and (3) PSA.MethodsWe searched PubMed and Embase for studies until 02 October 2017 and obtained individual participant data from four studies. In total, 78 studies were identified for the association between BMI and prostate cancer, 21 for BMI and advanced prostate cancer, and 35 for BMI and PSA. We performed random-effects meta-analysis of linear associations of log-PSA and prostate cancer with BMI and, to examine potential non-linearity, of associations between categories of BMI and each outcome.ResultsIn the meta-analyses with continuous BMI, a 5 kg/m2 increase in BMI was associated with a percentage change in PSA of − 5.88% (95% CI − 6.87 to − 4.87). Using BMI categories, compared to normal weight men the PSA levels of overweight men were 3.43% lower (95% CI − 5.57 to − 1.23), and obese men were 12.9% lower (95% CI − 15.2 to − 10.7). Prostate cancer and advanced prostate cancer analyses showed little or no evidence associations.ConclusionThere is little or no evidence of an association between BMI and risk of prostate cancer or advanced prostate cancer, and strong evidence of an inverse and non-linear association between BMI and PSA. The association between BMI and prostate cancer is likely biased if missed diagnoses are not considered.

Highlights

Prostate cancer is the second commonest male cancer worldwide, [1] and the most commonly diagnosed cancer in men in the UK, with an estimated 47,151 diagnoses in 2015 [2]
We performed a systematic review in which we included original articles published in peer reviewed journals that measured an association between Body mass index (BMI) and total prostate cancer incidence and/or advanced prostate cancer; and studies that measured an association between BMI and prostate-specific antigen (PSA), including supplements and meeting abstracts; human randomized controlled trials (RCTs), case–control, cohort, crosssectional, and non-randomized experimental studies
Books, commentaries, letters, and animal and cell-line studies; studies examining pre-malignant disease if there was no mention of prostate cancer or PSA; studies where BMI was measured after diagnosis of prostate cancer, as this increases the likelihood of reverse causality; and studies that we considered to be at critical risk of bias

Summary

Introduction

Prostate cancer is the second commonest male cancer worldwide, [1] and the most commonly diagnosed cancer in men in the UK, with an estimated 47,151 diagnoses in 2015 [2]. Previous meta-analyses and reviews have suggested that BMI is not associated with prostate cancer [4, 5], positively associated with prostate cancer [6, 7], inversely associated with localized prostate cancer [8], and positively associated with advanced [8], aggressive [9], high-grade, and fatal prostate cancers [4] These metaanalyses were either limited to cohort studies [4, 5, 7, 8] or in need of updating [6, 7]. We sought to perform an updated review of the literature, including more studies, and examining non-linear associations

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