The primary independent variable was serum Vitamin D measured at ED enrollment. We used Vitamin D level at ED presentation to identify patients with pre-existing Vitamin D deficiency prior to hospitalization for an acute illness. Vitamin D deficiency was defined as a serum Vitamin D concentration <20 milligrams per deciliter .We collected blood in citrate anti-coagulated collection tubes immediately upon study enrollment. Tubes were placed on ice and centrifuged at 3000 g-force within one hour to isolate plasma. Samples were stored at -80C until batched Vitamin D measurements were performed using the Abbott Architect i2000 . We used the Charlson comorbidity index to quantify patient comorbid burden.8 The Acute Physiology Score of the Acute Physiology and Chronic Health Evaluation II score, including age, was used to quantify severity of illness.The presence of a CNS diagnosis was determined by two physician reviewers via medical record review. Any disagreement was adjudicated by a third physician reviewer. Of the 228 patients enrolled in the DELINEATE cohort, 30 patients did not have a surrogate present to complete the pre-illness IQCODE and 64 did not have blood collected at enrollment leaving 134 participants available for this analysis. The patient characteristics stratified by Vitamin D deficiency status can be seen in the Table. The median Vitamin D level at enrollment was 25 mg/dL and 41 patients met criteria for Vitamin D deficiency.Of the 134 patients, 25 died prior to the six month follow-up, four opted out of the follow-up at enrollment, 10 were lost to follow-up,indoor farming equipment and 18 were successfully followed-up but a surrogate was not readily available to complete the six-month IQCODE.
A total of 77 patients survived and had a six-month IQCODE. The interaction term between Vitamin D deficiency and preillness IQCODE interaction’s p-value was significant indicating that the relationship between Vitamin D deficiency and six-month IQCODE was modified by the preillness IQCODE. The Figure displays the multi-variable linear regression models between serum Vitamin D at ED enrollment and adjusted six-month cognition. Among patients with a preillness IQCODE of 3.13 , for every 1 mg/dL decrease in serum Vitamin D, the six-month IQCODE score significantly increased by 0.18 points after adjusting for pre-illness IQCODE and other potential confounders; this indicated that lower serum Vitamin D concentrations measured at ED enrollment was associated with poorer six-month cognition. Among those with an IQCODE of 4.313 , no association with Vitamin D deficiency was observed . Similarly, Vitamin D deficiency was significantly associated with worsening six-month cognition among older adults cognitively intact at baseline . No association with Vitamin D deficiency was seen in those with pre-illness cognitive impairment . Our findings suggest that Vitamin D deficiency is common among older patients presenting to the ED with an acute medical illness, and Vitamin D deficiency is associated with increased risk for LTCI among older adults who are cognitively intact prior to an acute illness. Unfortunately, no intervention exists to preserve long-term cognition after an acute illness. The first step toward discovering an intervention is to identify modifiable risk factors early on in the course of an acute illness, and this is the impetus for our study. Future studies should determine if early Vitamin D repletion in the ED improves cognitive outcomes in acutely ill older patients.
We also observed that the association between serum Vitamin D concentrations and six-month cognition was more prominent in patients with intact cognition at baseline. It is possible that Vitamin D deficiency in the setting of acute illness may more profoundly affect those with intact cognition. It is also possible that patients with intact cognition at baseline are more at risk for cognitive decline following acute illness that is detectable with the measures currently available to assess cognition. Future studies should confirm this finding using more robust neuropsychiatric evaluations to quantify long-term cognition. Our study builds upon the work conducted in the outpatient settings, which also reported that low- serum Vitamin D level is associated with the development of Alzheimer’s disease.4 Because systemic and CNS Figure. The relationship between serum Vitamin D concentrations measured at enrollment and 6-month cognition. Cognition was determined by the short Informant Questionnaire on Cognitive Decline in the Elderly which ranged from 1 to 5 . The association between serum Vitamin D and 6-month cognition was modified by pre-illness cognition. In older adults with pre-illness cognitive impairment , serum Vitamin D concentrations were not a predictor of adjusted 6-month cognition. In older adults who were cognitively intact at baseline , there was a statistically significant relationship between serum vitamin D concentrations and 6-month cognition after adjusting for confounders. inflammation are the underpinning of LTCI pathophysiology, we hypothesize that Vitamin D treatment could potentially improve long-term cognition by attenuating systemic and CNS inflammatory responses. Vitamin D is a pleiotropic secosteroid hormone that modulates systemic and CNS inflammatory responses.Inflammation in response to an acute illness plays a prominent role in LTCI pathogenesis.
Vitamin D down regulates systemic inflammation by inhibiting the release of peripheral pro-inflammatory cytokines such as tumor necrosis factor-α , IL-6 and IL-12.Additionally, Vitamin D also inhibits CNS inflammation by attenuating systemic inflammation and more directly by specifically targeting the brain. Based upon in-vitro models, Vitamin D further attenuates CNS inflammation by inhibiting microglial production of pro-inflammatory cytokines such as IL-6 and TNF-α.14Emergency department over utilization costs the U.S. healthcare system nearly $38 billion annually.ED recidivism by older adult patients is a substantial contributing factor to ED over utilization with estimated rates varying between nearly 20% to over 40%, depending on time elapsed since the index ED visit, 30 days to six months, respectively.Older adults have more comorbid conditions and complex medical histories as compared to younger adults, often necessitating more expensive and lengthy ED diagnostic testing.Their utilization of the ED despite having health insurance and a primary care physician, suggests other contributors, such as poor health literacy, cognitive impairment, and lack of social support.Understanding the factors leading to ED recidivism in older adults is necessary to build prevention strategies to decrease unnecessary testing, over utilization of healthcare resources, and hospital admissions. High rates of recidivism coupled with the projected rise in the older adult population makes it critical that effective prevention strategies targeting older adults are developed.This narrative review will discuss risk factors for ED recidivism in older adults.Several diagnoses in older adults are associated with ED returns . Diagnoses most commonly reported as predictive of recidivism include those related to the respiratory system, hemp drying racks traumatic injuries, and pain . Respiratory diagnoses were found to be predictive not only of 30-day recidivism but of frequent recidivism .It is possible that the association of respiratory diagnoses with ED recidivism may reflect the season in which the studies were conducted. Information regarding the time of year the studies were conducted or whether a large percentage of the study population were enrolled in the fall and winter months is not available. Another possibility is that patients with respiratory diagnoses may have underlying chronic respiratory conditions such as emphysema or asthma and that these patients represent a sicker population. Common ED complaints in older adults include abdominal and chest pain. According to the National Health Statistics Reports of 2007, abdominal pain was the third most common reason for ED visits among all adults aged 65 years or older.Many patients presenting to the ED with abdominal pain or chest pain often do not receive a definitive diagnosis for the cause of their complaint despite extensive diagnostic testing. While clinicians feel safe discharging a patient with negative test results, believing that testing did not reveal any cause for emergent treatment or admission, this news may produce the opposite effect in patients due to this diagnostic uncertainty and fear of the unknown cause of their complaints. This lack of diagnostic certainty may lead patients to return to the ED in the hope of finding an answer or out of fear if the symptoms return.
The psychological component experienced by patients during their ED encounters is often overlooked and is a potential area of focus for study and improvement. All types of pain appear to increase the odds of ED returns in older adults. Furthermore, pain complaints may be predictive of frequent returns , particularly in those discharged from the ED with a prescription opioid.Patients discharged with prescription opioids who are properly educated on prescription opioid medications may be less likely to experience opioid-related adverse events, potentially minimizing ED recidivismThe presence of certain comorbid conditions such as depression, heart disease, diabetes, stroke, and cancer also increase ED recidivism in older adults.Poor mental health, depression, and diabetes were predictive not only of 30-day returns but of frequent returns.A history of psychiatric disorders is a common risk factor identified in several studies with one reporting it as predictive of frequent ED visits .In a study of low-income, homebound older adults with depression, a positive association was found between the Hamilton Rating Scale for Depression scores and frequency of ED visits.Non-cardiac, non-traumatic body pain was the most common reason for recidivism in this older adult population suffering from depression, highlighting the well-established link between depression and pain. While the literature suggests that specific comorbid conditions are associated with increased recidivism, overall comorbidity burden, as measured by the Charlson Comorbidity Index, is not. Although intuitively it would seem that patients with high co-morbidity burden would be more likely to return to the ED, La Mantia et al. found no association between Charlson comorbidity scores and ED recidivism.The presence of chronic illness in older adults returning, often frequently, to the ED suggests that at baseline these high-risk patients are sicker with a high burden of comorbidities requiring treatment with multiple medications. This likely explains the reporting of polypharmacy as an independent predictor for 30-day ED returns in older adults.Additionally, recent hospitalization, an indicator of clinical illness severity, was also found to be an independent predictive factor for repeat and frequent ED visits in older adults.Reasons for returning to the ED in this older adult population suffering with chronic illness may stem from the following: seeking reassurance regarding their condition; noncompliance with treatment plans leading to complications; compliance with treatment plans but still developing complications from their condition; not understanding the course of their disease; or inadequate education regarding their discharge plan. These include lack of social support,marital status, and anxiety.Divorced, separated, or widowed patients have more than double the increased odds for early returns within 30 days; conversely, patients who never married were significantly less likely to return. An explanation proposed by McCusker et al. for this finding is that patients who never married are more self-sufficient and independent than those who are currently or have previously been married. Reporting a perceived lack of social support by the patient was predictive of both 30-day and frequent returns .6 Patients who are divorced, separated, or widowed may feel they have less social support than their married counterparts to assist in their healthcare needs. Other psychosocial factors reported in the literature include anxiety and substance abuse such as daily alcohol use. Naughton et al. found a 13% increase in the risk of revisits per one unit increase in anxiety scores on the Hospital Anxiety and Depression Scale.The association between anxiety and ED recidivism supported by the literature is not surprising, particularly when a patient may not receive a definitive cause for their symptoms. Patients may experience fear and uncertainty regarding their health leading to anxiety.This coupled with a perceived poor social support system may lead these patients to return to the ED when challenged with new healthcare issues or a perceived failure of current issues to resolve in a timely manner. Daily alcohol use is associated with a decrease in risk of 30-day returns.6 However, two large retrospective cohort studies of older adults reported that a general history of substance abuse was an independent predictor of frequent ED use .Unfortunately, individual analyses for each of the substances of abuse that were included in these latter studies were not reported, making comparison of these disparate study conclusions difficult. Thus, it is unknown if daily alcohol use might confer a different risk compared to other substances of abuse.The Institute of Medicine defines health literacy as “the degree to which individuals can obtain, process, and understand basic health information and services they need to make appropriate health decisions.In older adults, low health literacy has been linked to decreased use of preventative services, higher utilization of acute care settings and resources, and poorer health outcomes.