Heavy smoking can damage vision
Smoking more than 20 cigarettes a day can damage your vision, a study coauthored by a Rutgers researcher finds.
The research appears in the journal Psychiatry Research.
The Centers for Disease Control and Prevention estimates that 34.3 million adults in the United States currently smoke cigarettes and that more than 16 million live with a smoking-related disease, many of which affect the cardiovascular system.
The study included 71 healthy people who smoked fewer than 15 cigarettes in their lives and 63 who smoked more than 20 cigarettes a day, were diagnosed with tobacco addiction and reported no attempts to stop smoking. The participants were between the ages of 25 and 45 and had normal or corrected-to-normal vision as measured by standard visual acuity charts.
The researchers looked at how participants discriminated contrast levels (subtle differences in shading) and colors while seated 59 inches from a 19inch cathode-ray tube monitor that displayed stimuli while researchers monitored both eyes simultaneously.
The findings indicated significant changes in the smokers' red-green and blue-yellow color vision, which suggests that consuming substances with neurotoxic chemicals, such as those in cigarettes, may cause overall color vision loss. They also found that the heavy smokers had a reduced ability to discriminate contrasts and colors when compared to the non-smokers.
"Cigarette smoke consists of numerous compounds that are harmful to health, and it has been linked to a reduction in the thickness of layers in the brain, and to brain lesions, involving areas such as the frontal lobe, which plays a role in voluntary movement and control of thinking, and a decrease in activity in the area of the brain that processes vision," said co-author Steven Silverstein, director of research at Rutgers University Behavioral Health Care.
"Previous studies have pointed to long-term smoking as doubling the risk for age-related macular degeneration and as a factor causing lens yellowing and inflammation. Our results indicate that excessive use of cigarettes, or chronic exposure to their compounds, affects visual discrimination, supporting the existence of overall deficits in visual processing with tobacco addiction."
Although the research did not give a physiological explanation for the results, Silverstein said that since nicotine and smoking harm the vascular system, the study suggests they also damage blood vessels and neurons in the retina.
Silverstein said the findings also suggest that research into visual processing impairments in other groups of people, such as those with schizophrenia who often smoke heavily, should take into account their smoking rate or independently examine smokers versus non-smokers. Patients
receiving hormone therapy as part of their gender-transition treatment had an elevated risk for cardiovascular events, including strokes, heart attacks and blood clots, according to a study published in the American Heart Association's journal Circulation.
The results are based on analysis of medical records of 3,875 Dutch individuals who received hormone treatment between 1972and 2015 as part of their gender transition.
"In light of our results, we urge both physicians and transgender individuals to be aware of this increased cardiovascular risk," said study author Nienke Nota, M.D., a researcher in the department of endocrinology at the Amsterdam University Medical Center. "It may be helpful to reduce risk factors by stopping smoking, exercising, eating a healthy diet and losing weight, if needed before starting therapy, and clinicians should continue to evaluate patients on an ongoing basis thereafter."
Past research has shown that hormone therapy increases cardiovascular risk among people receiving it to alleviate symptoms of menopause, yet research evidence remains scarce on the effects of hormone treatment in people undergoing gender transition. Even though such individuals tend to be younger than menopausal patients receiving hormone-replacement therapy, transgender people may have more psychosocial stressors and other factors that increase cardiovascular risk, the researchers said.
The analysis involved 2,517 transgender women, median age 30, who received estrogen, with or without androgen-suppressors, and 1,358 transgender men, median age 23, who received testosterone as part of their transition.
To gauge risk, the researchers determined the incidence of acute cardiovascular events -- heart attacks, strokes and deep vein thromboses (blood clots).