Hypertension and the risk of prostate cancer among type 2 diabetes mellitus subjects in northern nigeria

Background: Recent studies have found a significantly reduced risk of prostate cancer among diabetic subjects however, similar relationships with hypertension or other cardio metabolic factors have not been documented conclusively especially among Nigerians.
Objective: The aim of the study is to establish the relationship between hypertension and the risk of prostate cancer and other related factors among diabetics and non diabetic subjects.
Methods: The study was a cross sectional conducted among male diabetic patients in a tertiary hospital in northern Nigeria. The subjects comprises 122 subjects mean age 53.5(11.6) years, range 34 to 73 years and 76 matched control subjects.
Simple convenient sampling technique was used. The study protocols was approved by the hospital ethics committee.
The data obtained included personal, blood pressure and anthropometric measurements while lipids, glucose and serum total prostate specific antigen (PSA) were determined using ELISA technique.
Serum PSA levels of >5.0 ng/ml is considered as risk of prostate cancer. Blood pressure reading of >140/90 mmHg is considered hypertension.
The data was analysed using SPSS 23 version.
Results: Among the 122 diabetic subjects screened, 62 were hypertensive (SBP=137±22.9) and 60 normal (SBP=116±12.6) and the mean ages were 55.9(7.9) years and 51.1(14.4) years p<0.05.
The mean serum PSA was lower in hypertensive group 2.02(1.71) than in Diabetic only group 4.00(2.56) ng/ml p<0.05 while duration of disease was high among the hypertensive group p>0.05.
The correlation analysis shows that PSA has a significant negative relationship between SBP, DBP and FBG in experimental group while in control group similar pattern was found with rising SBP.p<0.05
Multiple regression analysis indicates that SBP and FBG predicts PSA negatively in the study subjects F(3, 116)=5.318, Anova p=0.02. Also SBP and FBG predicts PSA negatively and positively among the control group respectively (2, 117)=3.762, Anova p-0.026.
Conclusions: Systolic hypertension is associated with reduced total serum PSA levels among both the diabetic and non diabetic subjects. This will tend to have masking effect when screening for prostate cancer among diabetic hypertensive.