Having psoriasis appears to double the risk that a person will also have a dangerous clustering of risk factors for heart disease and diabetes known as metabolic syndrome, a new study shows. Previous research has found patients with psoriasis to be at higher risk for getting diabetes and high blood pressure, but the new study, which is in the Archives of Dermatology, is one of the first to document the broader complement of cardiovascular risks associated with the disease.
“It is more than skin deep,” says Abrar Qureshi, MD, MPH, co-author of the paper and vice chairman of the department of dermatology at Brigham and Women's Hospital in Boston. “We like to tell patients that psoriasis is a systemic disease. The risk for metabolic syndrome is high.”
Psoriasis is an autoimmune disease in which the body overproduces skin cells, causing a thick, scaly, red rash to appear on the palms, soles of the feet, elbows, scalp, or lower back. It is thought to be one manifestation of chronic, body-wide inflammation. Metabolic syndrome is defined as having at least three of the following risk factors for heart disease and diabetes: high blood pressure, too much belly fat, high fasting blood sugar, low levels of HDL “good” cholesterol, and high levels of bad blood fats called triglycerides. Studies have shown that having metabolic syndrome dramatically increases the risk of heart attacks, strokes, peripheral vascular disease, and type 2 diabetes.
Researchers say it's difficult to know which of the two might be driving the other. “There's evidence on both sides of the fence,” says lead study author Thorvardur Jon Löve, MD, of Landspitali University Hospital in Reykjavik, Iceland. “There's evidence that obesity drives the development of psoriasis. There's also evidence that inflammation drives some components of insulin resistance. It's a real chicken and egg problem at this point.”
Metabolic Syndrome and Psoriasis
The new study used blood test results from nearly 2,500 people who participated in the government-sponsored National Health and Nutrition Examination Survey between 2003 and 2006. None had previously been diagnosed with diabetes. Among study participants who said that a doctor had diagnosed them with psoriasis, 40% had metabolic syndrome, compared to just 23% of those who did not have psoriasis.
The association was particularly strong in women. Nearly half of women with psoriasis had metabolic syndrome, compared to just one in 5 women without psoriasis. In contrast, psoriasis appeared to raise a man's risk of having metabolic syndrome by only about 4%. “When you get this constellation of factors together, the risk is higher than the sum of the individual factors,” Löve says. “Visit your primary care physician and bring this up.”
Many people snore. Many people have heart attacks. Researchers from the University of Pittsburgh say they have found a connection between the two conditions. “People often report in primary care offices that they or their spouse complains of loud snoring, that they have difficulty falling asleep or staying asleep. And we as sleep researchers were interested in how this broad array of sleep symptoms that are often reported might relate to later cardiovascular risk,” lead research author Wendy Troxel of the University of Pittsburgh School of Medicine said.
Previous research has looked at the link between heart disease and obstructive sleep apnea, a problem where excess tissue blocks the airway during sleep. But this study looked purely at snoring. “There are some people with loud snoring who don't have obstructive sleep apnea,” Troxel continued.
In Troxel's government-funded study, more that 800 relatively healthy people ages 45 to 78 were followed for three years. High blood sugar and low levels of good cholesterol, both risk factors for heart disease, were twice as likely to present in the participants who reported frequent, loud snoring.
In addition to snorers, participants who had trouble falling asleep and had unrefreshing sleep were also at increased risk for metabolic syndrome, when additional heart disease risk factors like obesity, high blood pressure, and high levels of triglyceride fats are present. “Sleep complaints aren't just benign annoyances but something that can really foretell important health consequences,” Troxel stressed, “and they should really be discussed with [medical] providers and referred for further treatment if necessary.”
The research conducted at Pitt was an observational study. Patients were not treated to see whether decreasing snoring could lower the risk of heart disease. Rather, the study shows that snorers should pay particular attention to their heart disease risk factors.
The new study looked into the effects of four different diet combinations on blood lipid metabolism, in 117 patients with metabolic syndrome.
In accordance with previous suggestions, the researchers found that a low-fat, high-complex carbohydrate diet had “several detrimental effects”, including significantly increasing total triglyceride levels, and triglyceride rich lipoprotein cholesterol levels.
In contrast, intake of the same diet supplemented with omega-3 was found to have no effects on blood lipid levels, with researchers observing that a diet rich in monounsaturated fats, or a low-fat diet rich in complex carbohydrates and omega-3 fatty acids, resulted in lower circulating blood lipid levels than a diet rich in high saturated fats or a diet low in fats and high in complex carbohydrates.
The data from the study suggest a place for higher omega-3 intake in people with metabolic syndrome, and supports previous research that suggests monounsaturated fatty acids can have a positive effect on blood lipid levels.
“The long-term effect of the low-fat, high-complex carbohydrate diet, pre vs. post intervention phases, showed several beneficial effects of long chain omega-3 PUFA supplementation,” stated the researchers.
“Our data suggest that long-term intake of an isocaloric, low-fat, high-carbohydrate diet supplemented with long chain omega-3 … have beneficial effects on postprandial lipoprotein response in patients with metabolic syndrome,”
Source: The Journal of Nutrition
“A Low-Fat, High-Complex Carbohydrate Diet Supplemented with Long-Chain (n-3) Fatty Acids Alters the Postprandial Lipoprotein Profile in Patients with Metabolic Syndrome”
Authors: Y. Jimenez-Gomez, C. Marin, P. Perez-Martinez, et al
To examine this thesis, Froy and his colleagues, Ph.D. student Maayan Barnea and Zecharia Madar, the Karl Bach Professor of Agricultural Biochemistry, tested whether the clock controls the adiponectin signaling pathway in the liver and, if so, how fasting and a high-fat diet affect this control. Adiponectin is secreted from differentiated adipocytes (fat tissue) and is involved in glucose and lipid metabolism. It increases fatty acid oxidation and promotes insulin sensitivity, two highly important factors in maintaining proper metabolism.
The researchers fed mice either a low-fat or a high-fat diet, followed by a fasting day, then measured components of the adiponectin metabolic pathway at various levels of activity. In mice on the low-fat diet, the adiponectin signaling pathway components exhibited normal circadian rhythmicity. Fasting resulted in a phase advance. The high-fat diet resulted in a phase delay. Fasting raised and the high-fat diet reduced adenosine monophosphate-activated protein kinase (AMPK) levels. This protein is involved in fatty acid metabolism, which could be disrupted by the lower levels.
In an article soon to be published by the journal Endocrinology, the researchers suggest that this high-fat diet could contribute to obesity, not only through its high caloric content, but also by disrupting the phases and daily rhythm of clock genes. They contend also that high fat-induced changes in the clock and the adiponectin signaling pathway may help explain the disruption of other clock-controlled systems associated with metabolic disorders, such as blood pressure levels and the sleep/wake cycle.