Defining and measuring multimorbidity: a systematic review of systematic reviews.

Background: Multimorbidity, the coexistence of multiple health conditions, is a growing public health challenge. Research and intervention development are hampered by the lack of consensus regarding defining and measuring multimorbidity. The aim of this systematic review was to pool the findings of systematic reviews examining definitions and measures of multimorbidity. Methods: Medline, Embase, PubMed and Cochrane were searched from database inception to February 2017. Two authors independently screened titles, abstracts and full texts and extracted data from the included papers. Disagreements were resolved with a third author. Reviews were quality assessed. Results: Of six reviews, two focussed on definitions and four on measures. Multimorbidity was commonly defined as the presence of multiple diseases or conditions, often with a cut-off of two or more. One review developed a holistic definition including biopsychosocial and somatic factors as well as disease. Reviews recommended using measures validated for the outcome of interest. Disease counts are an alternative if no validated measure exists. Conclusions: To enable comparison between studies and settings, researchers and practitioners should be explicit about their choice of definition and measure. Using a cut-off of two or more conditions as part of the definition is widely adopted. Measure selection should be based on tools validated for the outcome being considered. Where there is no validated measure, or where multiple outcomes or populations are being considered, disease counts are appropriate.

Physical disease and resilient outcomes: a systematic review of resilience definitions and study methods.

BACKGROUND: Findings from physical disease resilience research may be used to develop approaches to reduce the burden of disease. However, there is no consensus on the definition and measurement of resilience in the context of physical disease. OBJECTIVE: The aim was to summarize the range of definitions of physical disease resilience and the approaches taken to study it in studies examining physical disease and its relationship to resilient outcomes. METHODS: Electronic databases were searched from inception to March 2013 for studies in which physical disease was assessed for its association with resilient outcomes. Article screening, data extraction, and quality assessment were carried out independently by 2 reviewers, with disagreements being resolved by a third reviewer. The results were combined using a narrative technique. RESULTS: Of 2280 articles, 12 met the inclusion criteria. Of these studies, 1 was of high quality, 9 were of moderate quality, and 2 were low quality. The common findings were that resilience involves maintaining healthy levels of functioning following adversity and that it is a dynamic process not a personality trait. Studies either assessed resilience based on observed outcomes or via resilience measurement scales. They either considered physical disease as an adversity leading to resilience or as a variable modifying the relationship between adversity and resilience. CONCLUSION: This work begins building consensus as to the approach to take when defining and measuring physical disease resilience. Resilience should be considered as a dynamic process that varies across the life-course and across different domains, therefore the choice of a resilience measure should reflect this.

Charlson index scores from administrative data and case-note review compared favourably in a renal disease cohort.

BACKGROUND: The Charlson index is a widely used measure of comorbidity. The objective was to compare Charlson index scores calculated using administrative data to those calculated using case-note review (CNR) in relation to all-cause mortality and initiation of renal replacement therapy (RRT) in the Grampian Laboratory Outcomes Mortality and Morbidity Study (GLOMMS-1) chronic kidney disease cohort. METHODS: Modified Charlson index scores were calculated using both data sources in the GLOMMS-1 cohort. Agreement between scores was assessed using the weighted Kappa. The association with outcomes was assessed using Poisson regression, and the performance of each was compared using net reclassification improvement. RESULTS: Of 3382 individuals, median age 78.5 years, 56% female, there was moderate agreement between scores derived from the two data sources (weighted kappa 0.41). Both scores were associated with mortality independent of a number of confounding factors. Administrative data Charlson scores were more strongly associated with death than CNR scores using net reclassification improvement. Neither score was associated with commencing RRT. CONCLUSION: Despite only moderate agreement, modified Charlson index scores from both data sources were associated with mortality. Neither was associated with commencing RRT. Administrative data compared favourably and may be superior to CNR when used in the Charlson index to predict mortality.

Relationship of EQ-5D quality of life with the presence of co-morbidity and extra-articular features in patients with rheumatoid arthritis.

PURPOSE: Rheumatoid arthritis (RA) is associated with extra-articular features (ExRA) and other co-morbidities. The aim of this study is to quantify their relative contribution to quality of life (QOL) in patients with RA. METHODS: A consecutive series of 114 ambulatory RA patients aged between 40 and 65 years were assessed by a research nurse on a single occasion. Assessment included a patient questionnaire (including EQ-5D), medication review and fasting venous blood sample. Medical records were reviewed by a rheumatologist for co-existing conditions. Multiple linear regression was used to adjust mean differences in EQ-5D in the presence/absence of co-existing conditions for age, sex, university education, arthritis duration, rheumatoid factor, erythrocyte sedimentation rate, current disease-modifying drug therapy, previous hand joint erosions and joint surgery. RESULTS: Mean age was 54 years (82% female) and median arthritis duration 10 years. Unadjusted EQ-5D was -0.09 (95% CI -0.18 to -0.01) lower in patients with any co-existing condition. EQ-5D scores were inversely correlated with the overall number of co-existing conditions (Spearman's ρ -0.31, p = 0.001), number of co-morbidities (ρ -0.22, p = 0.02) and number of ExRA features (ρ -0.22, p = 0.02). There was a linear trend of lower EQ-5D with increasing number of co-existing conditions (p = 0.003). EQ-5D was -0.18 (95% CI -0.33 to -0.02) lower in the presence of more than two co-existing conditions compared to none. Co-morbidity and ExRA features were associated with comparable adjusted reductions (-0.05 vs. -0.06) in EQ-5D scores. CONCLUSION: A wide range of co-existing conditions are associated with poorer QOL in patients with RA.

Inequalities in the distribution of the costs of alcohol misuse in Scotland: a cost of illness study.

AIMS: To examine the distribution of the costs of alcohol misuse across Scotland in 2009/2010, in relation to deprivation. METHODS: A cost of illness approach was used. Alcohol-related harmful effects were assessed for inclusion using a literature review. This was based upon the following categories: direct healthcare costs, intangible health costs, social care costs, crime costs and labour and productivity costs. An analysis of secondary data supplemented by a literature review was carried out to quantify each harmful effect, determine its value and provide an estimate of the distribution by deprivation. The deprivation distributions used were area measures (primarily the Scottish Index of Multiple Deprivation). RESULTS: The overall cost was £7457 million. Two alcohol harmful effects were not included in the overall cost by deprivation due to a lack of data. These were 'children's social work and hearing system' and the criminal justice system costs from 'alcohol-specific offences'. The included alcohol harmful effects demonstrated that 40.41% of the total cost arose from the 20% most deprived areas. The intangible cost category was the largest category (78.65%). CONCLUSION: The study found that the burden of alcohol harmful effects is greater in deprived groups and these burdens do not simply arise from deprived groups but are also experienced more by these groups. The study was limited by a lack of data availability in certain areas, leading to less-precise cost estimates.

Prevalence of secondary care multimorbidity in mid-life and its association with premature mortality in a large longitudinal cohort study.

OBJECTIVES: Multimorbidity is the coexistence of two or more health conditions in an individual. Multimorbidity in younger adults is increasingly recognised as an important challenge. We assessed the prevalence of secondary care multimorbidity in mid-life and its association with premature mortality over 15 years of follow-up, in the Aberdeen Children of the 1950s (ACONF) cohort. METHOD: A prospective cohort study using linked electronic health and mortality records. Scottish ACONF participants were linked to their Scottish Morbidity Record hospital episode data and mortality records. Multimorbidity was defined as two or more conditions and was assessed using healthcare records in 2001 when the participants were aged between 45 and 51 years. The association between multimorbidity and mortality over 15 years of follow-up (to ages 60-66 years) was assessed using Cox proportional hazards regression. There was also adjustment for key covariates: age, gender, social class at birth, intelligence at age 7, secondary school type, educational attainment, alcohol, smoking, body mass index and adult social class. RESULTS: Of 9625 participants (51% males), 3% had multimorbidity. The death rate per 1000 person-years was 28.4 (95% CI 23.2 to 34.8) in those with multimorbidity and 5.7 (95% CI 5.3 to 6.1) in those without. In relation to the reference group of those with no multimorbidity, those with multimorbidity had a mortality HR of 4.5 (95% CI 3.4 to 6.0) over 15 years and this association remained when fully adjusted for the covariates (HR 2.5 (95% CI 1.5 to 4.0)). CONCLUSION: Multimorbidity prevalence was 3% in mid-life when measured using secondary care administrative data. Multimorbidity in mid-life was associated with premature mortality.

Cohort profile: The prospective study on Chinese elderly with multimorbidity in primary care in Hong Kong.

PURPOSE: This is an ongoing prospective cohort aiming to examine the biopsychosocial health profiles and predictors of health outcomes of older patients with multimorbidity in primary care in Hong Kong. PARTICIPANTS: From April 2016 to October 2017, 1077 patients aged 60+ years with at least two chronic diseases were recruited in four public primary care clinics in the New Territories East Region of Hong Kong. FINDINGS TO DATE: After weighting, the patients had 4.1 (1.8) chronic conditions and 2.5 (1.9) medications on average; 37% forgot taking medication sometimes; 71% rated their health as fair or poor; 17% were frail; 73% reported one (21%) or two or more (52%) body pain areas; 62% were overweight/obese; 23% reported chewing difficulty, 18% reported incontinence; 36% had current stage 1/2 hypertension; 38% had handgrip strength below the cut-off; 10% screened positive in sarcopenia; 17% had mild or severer cognitive impairment; 17% had mild to severe depression; 16% had mild to severe anxiety; 50% had subthreshold to severe insomnia; 28% indicated being lonely; 12% needed help in at least one out of the five daily functions and the EuroQoL-5-Dimensions-5-Level index score was 0.81 (0.20) and its Visual Analogue Scale (VAS) score was 67.6 (14.6). In the past 12 months, 17% were hospitalised, 92% attended general outpatient clinics, 70% attended specialist outpatient clinics and 10% used elderly daycare centre services, the median out-of-pocket health cost was HK$1000 (US$150). Female and male patients showed significant differences in many biopsychosocial health aspects. FUTURE PLANS: With assessments and clinical data, the cohort can be used for understanding longitudinal trajectories of biopsychosocial health profiles of Chinese older patients with multimorbidity in primary care. We are also initially planning cohort studies on factors associated with various health outcomes, as well as quality of life and healthcare use. COHORT REGISTRATION NUMBER: ChiCTR-OIC-16008477.

Impact of educational attainment on the association between social class at birth and multimorbidity in middle age in the Aberdeen Children of the 1950s cohort study.

OBJECTIVE: Multimorbidity (the coexistence of two or more health conditions) is increasingly prevalent. No long-term cohort study has examined the impact of contemporaneously measured birth social class along with educational attainment on adult self-reported multimorbidity. We investigated the impact of educational attainment on the relationship between social class at birth and adult self-reported multimorbidity in the Aberdeen Children of the 1950s (ACONF) cohort. METHODS: A prospective cohort study using the ACONF cohort. ACONF included 12 150 individuals born in Aberdeen, Scotland 1950-1956. In 2001, 7184 (64%) responded to a questionnaire providing information including self-reported morbidity and educational attainment. The exposure was father's social class at birth from birth records and the outcome was self-reported multimorbidity.Logistic regression assessed the association between social class and multimorbidity with adjustment for gender, then by educational attainment and finally by childhood cognition and secondary school type. ORs and 95% CIs were presented. RESULTS: Of 7184 individuals (mean age 48, 52% female), 5.4% reported multimorbidity. Birth social class was associated with adult multimorbidity. For example, the OR of multimorbidity adjusted by gender was 0.62 (95% CI 0.39 to 1.00) in the highest social class group (I/II) in relation to the reference group (III (manual)) and was 1.85 (95% CI 1.19 to 2.88) in the lowest social class group. This was partially attenuated in all social class categories by educational attainment, for example, the OR was 0.74 (95% CI 0.45 to 1.21) in group I/II following adjustment. CONCLUSION: Lower social class at birth was associated with developing multimorbidity in middle age. This was partially mediated by educational attainment and future research should consider identifying the other explanatory variables. The results are relevant to researchers and to those aiming to reduce the impact of multimorbidity.