Prostate cancer (PCa) is the second most common cancer in men worldwide and the second leading cause of cancer deaths in men in the United States. Vitamin D is considered to have anticancer properties, currently thought to work mainly through its nuclear receptor or vitamin D receptor. In this retrospective study, we compared vitamin D levels in subjects with PCa with those of age-matched men without PCa. Study subjects included 479 in each group with a mean age of 73 and a mean creatinine of 1.05 and 1.15. Levels of 25 (OH) vitamin D were
Prostate cancer is the most commonly diagnosed cancer in men in the United States [
This is a clinical, retrospective study to evaluate vitamin D levels in subjects with or without prostate cancer. This study was approved by the Institutional Review Board as well as Research and Development at Stratton VA Medical Center at Albany, NY, USA. Subjects included patients whose vitamin D levels had been analyzed at Veterans Integrated Service Network (VISN-2) of Veterans Health Administration (VHA) between 2006 and 2009. Patients with end-stage kidney disease and chronic kidney disease, defined as having serum creatinine levels greater than 2.5 mg/dL, were excluded. Using the Current Procedural Terminology (CPT) codes for diagnosis of prostate cancer and the exclusion criteria for the study, 479 subjects with a diagnosis of prostate cancer were identified from review of approximately 5,000 patient records. The dates of diagnosis of prostate cancer were from 1994 to 2011. An additional 479 subjects without diagnoses of prostate cancer were age matched to the prostate cancer group and included in the study.
The following data was retrieved from the Computerized Patient Record System for all subjects: age, BMI, history of diabetes and hypertension, HbA1C, glucose, creatinine, estimated glomerular filtration rate (eGFR), 25 (OH) vitamin D; 1,25 (OH) vitamin D levels, calcium, and PTH.
The data is presented as
Study subjects include 479 with prostate cancer and 473 subjects without prostate cancer. Clinical data of subjects with and without prostate cancer is shown in Table
Clinical parameters in subjects with prostate cancer compared to age-matched controls without prostate cancer.
Clinical data in subjects with and without prostate cancer | |||
---|---|---|---|
P. Ca | No P. Ca |
|
|
Age (years) | 73 ± 0.4 | 74 ± 0.4 | 0.81 |
BMI | 29.1 ± 0.23 | 29.3 ± 0.27 | 0.66 |
DM (%) | 36 | 42 | 0.05 |
HTN (%) | 85 | 86 | 0.77 |
P. Ca: prostate cancer; BMI: body mass index; DM: diabetes; HTN: Hypertension.
Biochemical data in subjects with prostate cancer compared to age matched controls without Prostate cancer.
Biochemical data in subjects with and without prostate cancer | |||
---|---|---|---|
P. Ca | No P. Ca |
|
|
Vitamin D (ng/dL) | 28.4 ± 0.53 | 28.1 ± 0.63 | 0.68 |
Creatinine | 1.15 ± 0.02 | 1.07 ± 0.02 | 0.02 |
eGFR (mL/min) | 72 ± 0.86 | 81 ± 1.3 | <0.001 |
Calcium (mg/dL) | 9.5 ± 0.01 | 9.5 ± 0.02 | NS |
Glucose (mg/dL) | 114 ± 1.6 | 119 ± 2 | 0.03 |
HbA1C | 6.4 ± 0.057 | 6.6 ± 0.07 | 0.07 |
PTH (pg/mL) | 74 ± 7 | 81 ± 7 | 0.53 |
1,25, (OH) Vit. D (pg/mL) | 47 ± 6.8 | 47 ± 7.1 | 0.99 |
P. Ca: prostate cancer; eGFR: calculated glomerular filtration rate; PTH: Parathyroid hormone; 1,25, (OH) Vit. D: 1,25 (OH) vitamin D;
The most important point in the study is that there is no significant difference in the vitamin D levels between the subjects with and without prostate cancer when age matched. These results vary from epidemiological observations that have suggested links between low vitamin D and increased risk of prostate cancer. Calcitriol, the biologically active form of vitamin D (1,25(OH)D), has been shown to be an antiproliferative, prodifferentiation, proapoptotic agent, and an inhibitor of cell migration. Vitamin D deficiency is associated with an increased risk and poor prognosis of several types of cancer. Meta-analysis of genomic studies on the association between the two most studied VDR polymorphisms (FokI and BsmI) have shown significantly higher risk of cancer when the researchers pooled estimates from cancer sites possibly associated with vitamin D levels (prostate, breast, skin, ovary, non-Hodgkin lymphoma) [
Our results, showing no correlation between vitamin D levels and prostate cancer, are similar to recent data of some publications. The findings of the NIH epidemiological study noted that this large prospective study did not support the hypothesis that vitamin D is associated with decreased risk of prostate cancer; indeed, higher circulating 25(OH)D concentrations may be associated with increased risk of aggressive disease [
Ultraviolet-induced synthesis of vitamin
Our data on all subjects combined is consistent with the results of several publications that the vitamin D levels negatively correlate with BMI [
In the subanalysis of the data from prostate cancer subjects, we noted association of vitamin D levels with glucose and HbA1C levels. Most of the subjects with prostate cancer receive androgen deprivation therapy. Metabolic effects of androgen deprivation therapy for prostate cancer include insulin resistance, diabetes, dyslipidemia, adverse body composition, and metabolic syndrome that contribute to increase in cardiovascular mortality in this population [
Loss of bone mineral density is a well-known consequence of androgen deprivation therapy in men with prostate cancer [
This was a retrospective study. Comorbidities were not looked into. In some cases, vitamin D analysis was done prior to the diagnosis of prostate cancer and in others, after the diagnosis of prostate cancer. There was no attempt to account for this or compare results based on when the vitamin D levels were measured.
Vitamin D levels are similar in elderly men with or without prostate cancer.
The views expressed in this paper are those of the authors and do not necessarily reflect the position or policy of the Department of Veterans Affairs or the United States government.
This material is the result of work supported with resources and the use of facilities at the Stratton VA Medical Center at Albany, New York. S. Yaturu receives salary support from VA.