Increased lifespan, decreased mortality, and delayed cognitive decline in osteoarthritis

Rheumatic and Musculoskeletal Diseases and Risk of Dementia: A Nested Case-Control Study

OBJECTIVE

To investigate the associations between rheumatic and musculoskeletal diseases (RMDs) and incident dementia using population register-based data.

METHODS

This nested case-control study was conducted based on a cohort of residents in the Skåne region, Sweden, aged 50 years and older in 2009 without doctor-diagnosed dementia during 1998 to 2009 (n = 402,825). Individuals with a new main diagnosis of dementia during 2010 to 2019 were identified as incident patients with dementia (n = 22,131). Controls without diagnosed dementia were randomly matched 1:1 by sex, age, and Elixhauser comorbidity index using incidence density sampling. Separate conditional logistic regression analyses adjusted for confounders were fitted for the following RMDs, diagnosed at least 2 years before dementia diagnosis as exposure: gout, osteoarthritis, rheumatoid arthritis, spondyloarthropathies (SpA), and systemic connective tissue disorders. Subgroup analyses by dementia subtype, sex, age, comorbidity, and RMDs/dementia identification were conducted.

RESULTS

Although gout (adjusted rate ratio 0.88; 95% confidence interval 0.79-0.97), osteoarthritis (0.92; 0.88-0.96), and systemic connective tissue disorders (0.91; 0.83-0.99) were associated with decreased risk of dementia, the associations for rheumatoid arthritis (1.05; 0.92-1.19) and SpA (1.17; 0.94-1.45) were inconclusive. The associations between RMDs and incident dementia were similar across sex, age, and comorbidity subgroups with a few exceptions (eg, an adjusted rate ratio of 0.99 [95% confidence interval 0.71-1.39] in males vs 1.31 [0.99-1.74] in female patients for SpA).

CONCLUSION

Persons with diagnosed RMDs seem to have comparable or slightly lower risks of developing dementia compared with those without known RMD.

The efficacy and safety of leucine-enriched essential amino acids in knee osteoarthritis patients: A randomized controlled trial

BACKGROUND

Supplementation with leucine-enriched essential amino acids (LEAAs) has shown efficacy in the recovery of muscle injury and activation of muscle synthesis. Muscle function in knee osteoarthritis is a crucial factor for managing pain and preserving ambulatory function. However, the efficacy and safety of LEAAs supplementation in patients with knee osteoarthritis have not been evaluated.

METHODS

In this prospective analysis, we evaluated the efficacy and safety of supplementation with 12 g of LEAAs daily for 8 weeks in knee-symptomatic osteoarthritis patients. For assessing the efficacy, clinical pain, calf circumference, and disability were assessed using questionnaires (visual analog scale, Knee Society Score, and 36-item short form survey [SF-36]), laboratory analyses (total protein and albumin), and radiologic study (dual-energy X-ray absorptiometry [DEXA]) for muscle and bone density. To evaluate safety, generalized or localized protein allergic reactions, complete blood count, liver and kidney function, and serum glucose were measured.

RESULTS

Sixty-five participants, categorized into the experimental (n = 32) and control (n = 33) groups, were included in this 8-week trial from March 2022 to July 2022. A significantly higher efficacy was observed in the experimental group than in the control group, as indicated by muscle density in the DEXA scan (P = .001) and SF-36 (P < .001). The safety evaluation revealed no related generalized or local protein allergy. Hematological findings, serum glucose, and kidney and liver toxicity were not significantly different between the groups.

CONCLUSION

Supplementation with leucine-enriched proteins is safe and efficacious in the improvement of muscle density and quality of life.

Association of Osteoarthritis and Functional Limitations With Cognitive Impairment Among Older Adults in the United States

Objective: Given overlapping pathophysiology, this study sought to assess the association between osteoarthritis (OA), functional impairment, and cognitive impairment in the aging population. Methods: The National Health and Nutrition Examination Survey was used to identify participants >60 years of age. We analyzed multivariable associations of grouped participants that underwent cognitive function testing using linear and logistic regression, adjusting for sex, age, race, and ethnicity. Results: Of 2776 identified participants representing a population of 50,242,917, 40% did not report OA or functional limitations; 21% had OA but not functional limitations; 15% did not have OA but had functional limitations; 17% had OA and related functional limitations; and 7% had OA and non-arthritic functional limitations. OA was not independently associated with cognitive impairment. Contrarily, functional limitations were associated with cognitive impairment regardless of OA diagnosis. Discussion: Cognitive impairment is not associated with OA, but rather functional limitations, potentially guiding future intervention.

From Low-Grade Inflammation in Osteoarthritis to Neuropsychiatric Sequelae: A Narrative Review

Nowadays, osteoarthritis (OA), a common, multifactorial musculoskeletal disease, is considered to have a low-grade inflammatory pathogenetic component. Lately, neuropsychiatric sequelae of the disease have gained recognition. However, a link between the peripheral inflammatory process of OA and the development of neuropsychiatric pathology is not completely understood. In this review, we provide a narrative that explores the development of neuropsychiatric disease in the presence of chronic peripheral low-grade inflammation with a focus on its signaling to the brain. We describe the development of a pro-inflammatory environment in the OA-affected joint. We discuss inflammation-signaling pathways that link the affected joint to the central nervous system, mainly using primary sensory afferents and blood circulation via circumventricular organs and cerebral endothelium. The review describes molecular and cellular changes in the brain, recognized in the presence of chronic peripheral inflammation. In addition, changes in the volume of gray matter and alterations of connectivity important for the assessment of the efficacy of treatment in OA are discussed in the given review. Finally, the narrative considers the importance of the use of neuropsychiatric diagnostic tools for a disease with an inflammatory component in the clinical setting.

Synthesis of charged chitosan nanoparticles as functional biolubricant

Osteoarthritis has been a major disease in recent years, which is mainly related to the breakdown of the lubrication function of the cartilage sliding interface, along with the inflammation of the joint capsule. In this paper, one kind of novel biomimetic nanoparticles (NPs) lubricant, named CS-PS, is synthesized through chemically grafting hydrophilic sulfonic acid (SO₃^-) groups onto the surface of biocompatible and biodegradable chitosan (CS) NPs. Compared with control CS NPs, the as-synthesized CS-PS NPs exhibits excellent hydration and stability because of negatively charged surface zeta potential, along with extraordinary lubrication performance in water for realizing a super-low friction coefficient (COF) as ∼0.01 at the sliding interface of PDMS elastomer-Ti₆Al₄V disk. Correspondingly, the CS-PS NPs can also be used as a drug carrier for aspirin, which presents very good drug loading and release behavior in PBS (pH = 7.4). MCS cells culture experiment proves that this kind of novel lubricant is nontoxic and biocompatible, for which may be expected to use as potential articular injective material for the treatment of osteoarthritis.

Risk of comorbidities following physician-diagnosed knee or hip osteoarthritis: a register-based cohort study

OBJECTIVE

To estimate the risk of developing comorbidities in patients after physician-diagnosed knee or hip osteoarthritis (OA).

DESIGN

Cohort study using Swedish longitudinal healthcare register data; we studied residents in the Skåne region aged ≥35 years at January 1, 2010 free from diagnosed hip or knee OA (n= 548,681). We then identified subjects with at least one new diagnosis of knee or hip OA (incident OA) between 2010 and 2017 (n=50,942 considered exposed). Subjects without diagnosed OA were considered unexposed. From January 2010 both unexposed and exposed subjects were observed for the occurrence of 18 different pre-defined comorbidities until either relocation outside of the region, death, occurrence of the comorbidity, or December 2017, whichever came first. We calculated unadjusted and adjusted hazard ratios (HR, aHR) of comorbidities using Cox models with knee and hip OA as time-varying exposures.

RESULTS

Subjects with incident knee or hip OA had 7% to 60% higher adjusted hazards (aHR between 1.07 to 1.60), of depression, cardiovascular diseases, back pain, and osteoporosis than individuals without an OA diagnosis. An increased risk of diabetes was found only for knee OA (aHR 1.19, 95% CI 1.13-1.26). For the rest of the diagnoses, we found either no increased risk or estimates with wide confidence intervals, excluding clear interpretations of the direction or size of effects.

CONCLUSIONS

Incident physician-diagnosed knee and hip OA is associated with increased risk of depression, cardiovascular diseases, back pain, osteoporosis, and diabetes. However, the latter only for knee OA.

Common risk factors and therapeutic targets in obstructive sleep apnea and osteoarthritis: An unexpectable link?

Osteoarthritis (OA) and Obstructive Sleep Apnea (OSA) are two highly prevalent chronic diseases for which effective therapies are urgently needed. Recent epidemiologic studies, although scarce, suggest that the concomitant occurrence of OA and OSA is associated with more severe manifestations of both diseases. Moreover, OA and OSA share risk factors, such as aging and metabolic disturbances, and co-morbidities, including cardiovascular and metabolic diseases, sleep deprivation and depression. Whether this coincidental occurrence is fortuitous or involves cause-effect relationships is unknown. This review aims at collating and integrating present knowledge on both diseases by providing a brief overview of their epidemiology and pathophysiology, analyzing current evidences relating OA and OSA and discussing potential common mechanisms by which they can aggravate each other. Such mechanisms constitute potential therapeutic targets whose pharmacological modulation may provide more efficient ways of reducing the consequences of OA and OSA and, thus, lessen the huge individual and social burden that they impose.