The Impact of Asthma and Chronic Obstructive Pulmonary Disease (COPD) on Patient-Reported Outcomes in Systemic Lupus Erythematosus (SLE)

Comorbidities in Privately Insured South Africans With Systemic Lupus Erythematosus

Introduction Comorbidities in systemic lupus erythematosus (SLE) impact negatively on health-related quality of life (HRQoL) and life expectancy. We investigated the frequency and spectrum of comorbidities in privately insured South Africans with SLE. Methods The data of SLE patients based on International Classification of Diseases, Tenth Revision (ICD-10) codes and insured with Discovery Health Medical Scheme (DHMS), South Africa, aged ≥16 years at diagnosis and with ≥6 months of follow-up were reviewed. Demographics, comorbidities listed in the Charlson comorbidity index (CCI), other common comorbidities, intercurrent illnesses, and drug therapy were documented. Results Of the 520 patients coded as SLE, 207 met the inclusion criteria. Most were females (90.8%), with a median (interquartile range {IQR}) age and follow-up duration of 39 (30.3-53.0) and 6.1 (3.7-8.1) years, respectively. All patients had at least one comorbidity; the most frequent CCI comorbidities were pulmonary disease (30.9%), congestive heart failure (CHF, 15%), and renal disease (14.0%). Other common comorbidities were hypertension (53.1%) and mood and anxiety disorders (46.9%). Urinary tract infections (UTIs, 37.7%) and pneumonia (33.8%) were common intercurrent illnesses. The independent predictors of CHF were renal disease (odds ratio {OR}=855), dyslipidemia (OR=15.3), and male gender (OR=43.0); the independent predictors of hypertension were age at diagnosis (OR=1.03), type 2 diabetes (OR=4.45), and renal disease (OR=4.34); and the independent predictors of mood and anxiety disorders were female gender (OR=3.98), stroke (OR=3.18), UTI (OR=2.39), and chloroquine use (OR=1.94). Conclusion In this study of privately insured South Africans with SLE, comorbidities were common, and all patients had at least one comorbidity. Hypertension, infections, and mood and anxiety disorders were the leading comorbidities overall, and pulmonary disease was the most common CCI comorbidity. There is an obvious need to formally study the burden of mental health disorders in South African SLE patients.

Circadian Regulation of Apolipoproteins in the Brain: Implications in Lipid Metabolism and Disease

The circadian rhythm is a 24 h internal clock within the body that regulates various factors, including sleep, body temperature, and hormone secretion. Circadian rhythm disruption is an important risk factor for many diseases including neurodegenerative illnesses. The central and peripheral oscillators' circadian clock network controls the circadian rhythm in mammals. The clock genes govern the central clock in the suprachiasmatic nucleus (SCN) of the brain. One function of the circadian clock is regulating lipid metabolism. However, investigations of the circadian regulation of lipid metabolism-associated apolipoprotein genes in the brain are lacking. This review summarizes the rhythmic expression of clock genes and lipid metabolism-associated apolipoprotein genes within the SCN in Mus musculus. Nine of the twenty apolipoprotein genes identified from searching the published database (SCNseq and CircaDB) are highly expressed in the SCN. Most apolipoprotein genes (ApoE, ApoC1, apoA1, ApoH, ApoM, and Cln) show rhythmic expression in the brain in mice and thus might be regulated by the master clock. Therefore, this review summarizes studies on lipid-associated apolipoprotein genes in the SCN and other brain locations, to understand how apolipoproteins associated with perturbed cerebral lipid metabolism cause multiple brain diseases and disorders. This review describes recent advancements in research, explores current questions, and identifies directions for future research.

Updating and Validating the Rheumatic Disease Comorbidity Index to Incorporate ICD-10-CM Diagnostic Codes

OBJECTIVE

To update and validate the Rheumatic Disease Comorbidity Index (RDCI) utilizing International Classification of Diseases, Tenth Revision, Clinical Modification (ICD-10-CM) codes.

METHODS

We defined ICD-9-CM (n = 1,068) and ICD-10-CM (n = 1,425) era cohorts (n = 862 in both) spanning the ICD-9-CM to ICD-10-CM transition in a multicenter, prospective rheumatoid arthritis registry. Information regarding comorbidities was collected from linked administrative data over 2-year assessment periods. An ICD-10-CM code list was generated from crosswalks and clinical expertise. ICD-9- and ICD-10-derived RDCI scores were compared using intraclass correlation coefficients (ICC). The predictive ability of the RDCI for functional status and death during follow-up was assessed using multivariable regression models and goodness-of-fit statistics (Akaike's information criterion [AIC] and quasi information criterion [QIC]) in both cohorts.

RESULTS

Mean ± SD RDCI scores were 2.93 ± 1.72 in the ICD-9-CM cohort and 2.92 ± 1.74 in the ICD-10-CM cohort. RDCI scores had substantial agreement in individuals who were in both cohorts (ICC 0.71 [95% confidence interval 0.68-0.74]). Prevalence of comorbidities was similar between cohorts with absolute differences <6%. Higher RDCI scores were associated with a greater risk of death and poorer functional status during follow-up in both cohorts. Similarly, in both cohorts, models including the RDCI score had the lowest QIC (functional status) and AIC (death) values, indicating better model performance.

CONCLUSION

The newly proposed ICD-10-CM codes for the RDCI-generated comparable RDCI scores to those derived from ICD-9-CM codes and are highly predictive of functional status and death. The proposed ICD-10-CM codes for the RDCI can be used in rheumatic disease outcomes research spanning the ICD-10-CM era.