Morbidity causality

SI is the term given to cases of insomnia that appear to be secondary to other distressful conditions or secondary to substance use. Secondary in this context means that another condition causes and maintains the insomnia. Insomnia cases where no causal link exists, but where insomnia and another condition co-occur yet function independently, are referred to as co-morbid . If an insomnia state is clearly secondary to another condition, then presumably, the insomnia will subside if the primary condition is successfully treated, but data to support this SI conceptual scheme are scarce, calling into question the concept of causal influence in supposed SI. 

A major problem in interpreting the biological factors that are causally related to PTSD arises from the difficulty in differentiating the changes due to depression and drug abuse, which are common co-morbid conditions, and the limitation of most studies to combat victims. 

Hypolipidemic drugs are being developed with the assumption that reduction of elevated serum lipid is necessary in order to control mortality and morbidity associated with cardiovascular disease. Although the causal relationship between the level of certain serum lipids and the development of the atherosclerotic... 

Infectious diseases are common and result in significant morbidity and mortality in patients with ESKD. Although multiple abnormalities in host defenses and an increased susceptibility to infection have been described, the causal link between these observations remains speculative. Absolute lymphopenia and impaired cell-mediated immunity are common in ESKD patients and may be caused by uremic toxins or protein-calorie malnutrition. Although plasma concentrations of IgG, IgM, and IgA are usually normal, antibody responses appear to be significantly depressed. Patients requiring dialysis have many problems with vascular access which puts them at higher risk for exposure to infectious sources. The risk of infections in patients with CKD, and particularly ESKD, is an important consideration when reviewing the clinical presentation of a patient, as hospitalization rates for infection and sepsis have increased dramatically in the last 10 years. ... 

Evidence has grown over the last decade, that urban airborne particles at ambient concentration levels common in many cities in Europe, America and Asia exert adverse effects on human health. Short- or long-term exposure to particulate matter (measured as PMio or PM2.5) is associated with an increase risk of cardiovascular and respiratory morbidity and mortality. Collectively the toxicological and epidemiological studies provide sufficient evidence that a causal relationship is likely to exist between exposure to ambient concentrations of PMjo or PM2.5 and specific human morbidity (exacerbation of chronic bronchitis, asthma or coronary heart disease) and premature deaths. 

Insufficient sleep and insomnia have been identified as contributing to significant cardiovascular morbidity. The epidemic of obesity, diabetes, and metabolic syndrome may be attributed, at least partially, to sleep loss. Traffic accidents due to sleepiness are directly connected to sleep deprivation. OSA has been pointed out as causally related to hypertension. Depression gets better after insomnia is successfully treated with CBTI. Sleep disorders drive healthcare costs up. These findings represent a call to action make sleep evaluation and improvement a mission of modern society. A first step is happening now spread the news to educate the population. The next one is at its dawn offer affordable solutions to detect and improve sleep. Mobile technology has great potential to serve an important role in the fulfillment of this mission. 

Although the observational studies suggested modest associations of homocysteine with risk of vascular disease that were biologically plausible, such studies could not establish if these associations were causal. The randomized trials assessed the effectiveness of dietary supplementation with B vitamins to lower homocysteine levels on risk of cardiovascular morbidity and mortality. The initial trials were designed in the mid-1990s before the results of the Homocysteine Studies Collaboration meta-analysis (Homocysteine Studies Collaboration 2002) were reported in 2002. Consequently, few of the individual trials had sufficient statistical power to confirm or refute the 10% difference in... 

Whereas considerable effort has gone into the investigation of the effects of environmental irritants and allergens on changes in bronehial smooth-muscle tone, as indieated by FEVi, there is a dearth of information in the area of environmental toxieants effects on cardiac or cardiovascular performance. The potential profound effects of inhaled irritants and antigens on eardiovascular performance has been documented over several decades however, direct information relevant to the roles of these responses to the increase in morbidity and mortality in humans from inhaled particles and irritants is still awaiting causal verification. 

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