Comorbidities and Concomitant Medication Use in Men with Prostate Cancer or High Levels of PSA Compared to Matched Controls: A GPRD Analysis

Comorbidity influences screening practice, treatment choice, quality of life, and survival. The presence of comorbidities and medication use could place patients at greater risks of adverse effects from certain interventions. We conducted a longitudinal cohort study in the General Practice Research Database to better understand comorbidities and medication use in men with or at risk of prostate cancer (CaP). Compared with men with similar age but no CaP, CaP patients had higher incidence of urinary tract infection, impotence and breast disorder, and 2.6-fold higher all-cause mortality. Among men with elevated prostate-specific antigen (PSA) but no CaP, the mortality rates were slightly lower, and fewer differences in comorbidities and medication use were noted compared to men without elevated PSA. Many prevalent comorbidities and medications were consistent across groups and are typical of an older male population. These real-world data are broadly applicable throughout the drug development cycle and subsequent patient management. 1. Introduction Prostate cancer (CaP) is the most common nonskin cancer and the second or third leading cause of death from cancer among men in the developed world [1]. In the UK, more than 36,000 men are diagnosed with CaP each year, comprising a quarter of all cancers diagnosed in men. Although approximately 10,000 men died from CaP in the UK in 2008, survival rates for CaP patients have changed markedly over the past 40 years. More than 75% of CaP patients currently survive beyond five years, compared with less than a third of the patients with five-year survival in the 1970s; the differential is even greater in the ten-year survival experiences now compared to 40 years ago [2]. Thus, the CaP patient population is large. Moreover, in this large group, the burden of disease from CaP is preponderantl in elderly men, with men who are 70 years or older comprising more than half the patient population in the UK. Consequently, CaP patients often present for medical care with advanced age-related comorbidities [3]. The number and types of patient comorbidities have informed treatment choice for CaP in clinical practice, with less aggressive treatment used as comorbidity increases [4–9]. Comorbidity scores have been shown to predict outcomes ranging from late urinary complications [10] to overall survival [11] among men who have undergone radical prostatectomy. Moreover, specific comorbidities, or a high number of comorbidities, have been used in some instances to exclude patients from clinical trials due to concerns of increased