What Your Doctor Can't Tell You: Risk Factors For Prostate Cancer Do Not Include Smoking
An American boy born today faces a 15.3 percent risk of being diagnosed with prostate cancer at some point in his life, estimates the National Cancer Institute, and a 3 percent chance of dying from the disease. While the biggest risk factors for prostate cancer are age, race, and family history, a new study finds high blood pressure, high cholesterol, vitamin D deficiency, inflammation of the prostate gland, and a vasectomy also play a role in deciding which men will develop this disease.
Shockingly, smoking, obesity, and alcohol abuse were negatively associated with the dreaded disease.
What is the prostate?
The prostate is a gland found only in men. It sits beneath the bladder and surrounds the urethra, which is the tube that carries urine and semen through the penis. Usually the size and shape of a walnut, the prostate gland makes semen, the fluid that carries sperm. Some men with prostate cancer will have no symptoms, according to the website of Prostate Cancer UK, while others may experience:
- a need to pee more often, especially at night
- difficulty starting to urinate
- straining, or taking a long time to finish
- a weak flow
- a feeling that the bladder hasn’t emptied properly
- a need to rush to the toilet, and the occasional leak
- dribbling urine
Unfortunately, scientists don't know what causes this disease.
For the current study, Alqahtani and his co-researchers analyzed data from The U.S. Nationwide Inpatient Sample (NIS), the largest database of all-payer inpatient healthcare records. Specifically, the team focused on the years 2007 through 2011 which contained, all told, more than 12 million files. In particular, they investigated data from men between the ages of 35 and 100 years old.
Crunching the numbers, the researchers discovered a total of 642,383 men (about 5.4 percent) had been diagnosed with prostate cancer. Next, they looked at a range of possible variables to see which might be crucial to the development of the disease — age, race, family history of prostate cancer, family history of any other cancer, obesity, alcohol abuse, smoking, cholesterol, vitamin D deficiency, inflammation of the prostate gland, history of vasectomy, and hypertension.
“Men who are 65 years old and older are the majority of prostate cancer patients,” wrote Khaled Alqahtani, a Ph.D. student in the department of health informatics at Rutgers Biomedical and Health Sciences, and his colleagues. Age, then, is the most significant predictor of this disease, explained the researchers, adding the average age at diagnosis is 66, the average age group of diagnosis is ages 65 through 74. That said, this cancer can affect a man at any age.
After age, the biggest risk factor is family history.
“A family history of prostate cancer in either brother(s) or father raised cancer risk by 48 percent and 11 percent, respectively,” wrote the researchers.
Race is also key. Between 1975 and 2005, “African-American men were observed as those most likely to die from prostate cancer, specifically, above all other ethnic groups,” wrote Dr. Khaled Alqahtani, department of health informatics at Rutgers Biomedical and Health Sciences, and his colleagues. “Caucasian American men were recorded with the second highest mortality rate, followed by Native American, Hispanic, and then Asian/Pacific Islander ethnicities.”
While race, age, and family history were more or less expected, other findings from the study were surprising, to say the least. Obesity, alcohol abuse, and smoking were negatively associated with the disease, according to the researchers. In fact, past studies have shown heavy smokers are 24 percent to 30 percent less likely to die from prostate cancer than those who do not smoke.
However, a positive family history of another cancer, hypercholesterolemia (high levels of cholesterol), vitamin D deficiency, inflammation of the prostate gland, a vasectomy, and hypertension (high blood pressure) all showed a positive link to the disease. Specifically, men with hypercholesterolemia are 24.3 percent greater odds of developing prostate cancer, the results suggest, while a man with a vasectomy has 4.6 times greater chance (in both cases when compared to men without these histories).
“Further studies with more data details are needed in the future," concluded the authors. Meanwhile, younger men could only benefit from greater awareness of this disease and might want to read the American Cancer Society's recommendations for screening tests.
Source: Alqahtani KS, Srinivasan S, Mital DP, Haque S. Analysis of risk factors for prostate cancer patients. International Journal of Medical Engineering and Informatics. 2015.