Could vitamin D deficiency explain sepsis risk in elderly people?
Older patients with sepsis who were critically ill and hospitalized were more likely to experience severe cognitive impairment and abnormal physical decline years later, according to a recent study published in the Oct 27, 2010 issue of the Journal of the American Medical Association.
In response to the study, a health observer suggested that vitamin D deficiency may be at least partially responsible for sepsis and the worsened mental and physical decline in the patients hospitalized and treated for sepsis.
This case-control study led by Theodore J. Iwashyna, M.D., Ph.D., and colleagues at the University of Michigan was to compare the cognitive decline and physical limitations in patients hospitalized for sepsis and those without sepsis.
The study involved 516 people who survived 623 hospitalizations for severe sepsis between 1998 and 2006. The average age for hospitalization due to sepsis was 77.
The study shows that among those who were hospitalized for sepsis, 60 percent experienced worsened cognitive or physical function or both and sepsis patients who survived sepsis after hospitalization were 3.33 times more likely to worsen their mental status to moderate or severe cognitive impairment years later compared to the risk before hospitalization.
The study also found sepsis survivors who had no limitation before sepsis developed an average 1.57 new functional limitations. This is compared to 0.48 new functional limitations developed after hospitalization in patients without sepsis.
Hospitalization for non-sepsis conditions was not associated with elevated risk of cognitive decline and development of functional limitations.
The researchers estimated sepsis may be responsible for 20,000 new cases of dementia among people aged 65 years or older each year in the United States.
The study demonstrated that sepsis survivors face risk of severe cognitive decline and physical limitations years later. But it did not prove sepsis caused the worsening of cognitive function and physical limitations although it seemingly suggests that sepsis may cause the complications.
It could be that the increased risk of worsened mental decline result from medications used for sepsis or some underlying conditions in the hospitalized patients with sepsis.
Sepsis is a bloodstream infection. Young children, elderly people and those who have their immunity compromised are at high risk of sepsis because their immune systems are weakened or under development.
Vitamin D deficiency may be one risk factor for sepsis and its complications. Vitamin D, which is often found low in elderly people, has been associated in many studies with not only a person's vulnerability for infections, but also for cognitive decline.
Llewellyn DJ and colleagues from the University of Exeter in the United Kingdom reported a study in the July 12 2010 issue of Archives of Internal Medicine saying low levels of vitamin D were associated with substantial cognitive decline in the elderly population.
Numerous studies have suggested that Low vitamin D status was associated with a reduced capability for spatial working memory, increased risk of cognitive deficits or cognitive impairment, and dementia, particularly Alzheimer's disease.
Vitamin D deficiency may be a significant part responsible for the increased risk of worsened mental and physical conditions in sepsis patients, the health observer suggested.
Sufficient Vitamin D has been known to boost innate immunity by helping produce antimicrobial peptides, which are protective against infections induced by viruses and bacteria.
As a matter of fact, one study led by Jeng L. and colleagues from Emory University School of Medicine in Atlanta, GA and published in 2009 in Journal of Translational Medicine found that critically ill patients with sepsis had significantly lower plasma D25(OH)D), vitamin D binding protein and cathelicidin - an anti-microbial peptide. The study suggests that vitamin D may be responsible for sepsis.
No study has yet proved that taking vitamin D supplements may help elderly people reduce the risk of sepsis. But Grant W.B., an vitamin D expert suggested in the Feb 2010 issue of Early Human Development that "vitamin D supplementation of mother and infant could reduce risk of sepsis in premature infants." Could this nutrient work as well in elderly people to prevent sepsis?
According to the Centers for Disease Control and Prevention, the rate of hospitalization for sepsis or septicemia for people aged 65 to 74 increased 57 percent from 6.5 per 1,000 to 10.2 and the rate for those aged 75 to 84 increased 52 percent from 11.7 per 1000 to 17.8 during the period between 2000 and 2007.
Elderly people tend to be vitamin D deficient because they stay indoors more often and the production of vitamin D in these individuals is less efficient. Maintaining high levels of this nutrient may help prevent sepsis and dementia among other things.
By Jimmy Downs