Cross-sectional relationship between pain intensity and subjective cognitive decline among middle-aged and older adults with arthritis or joint conditions: Results from a population-based study

Introduction

We investigated cross-sectional relationships between arthritis or joint-related pain intensity and subjective cognitive decline in middle-aged and older adults.

Methods

The sample consisted of 30,150 adults ⩾age 45 years with self-reported arthritis or joint conditions who completed key variables in the 2015 wave of the Behavioral Risk Factor Surveillance System.

Results

Using weighted data, 94.2% of the sample reported experiencing joint pain in the last month (35.9% reported moderate pain and 30.6% reported severe pain) and 17.3% reported subjective cognitive decline. In logistic regression models, pain intensity was associated with significantly higher odds of reporting subjective cognitive decline, after controlling for age, race/ethnicity, sex, education, household income, cardiovascular health, mental health, and history of stroke. Those with moderate pain were two times as likely to report subjective cognitive decline and those with severe pain were more than three times as likely to report subjective cognitive decline relative to those without pain, adjusting for covariates.

Conclusion

The results of this study highlight a significant relationship between pain intensity and subjective cognitive decline in middle-aged and older adults with arthritis or joint conditions typically associated with joint pain. Moderate and severe joint pain is significantly associated with higher risk of subjective cognitive decline, after controlling for personal and health characteristics. Future studies with more comprehensive assessments of pain and cognition are warranted to further elucidate these relationships and their underlying mechanisms.

A genome-wide association search for type 2 diabetes genes in African Americans

African Americans are disproportionately affected by type 2 diabetes (T2DM) yet few studies have examined T2DM using genome-wide association approaches in this ethnicity. The aim of this study was to identify genes associated with T2DM in the African American population. We performed a Genome Wide Association Study (GWAS) using the Affymetrix 6.0 array in 965 African-American cases with T2DM and end-stage renal disease (T2DM-ESRD) and 1029 population-based controls. The most significant SNPs (n = 550 independent loci) were genotyped in a replication cohort and 122 SNPs (n = 98 independent loci) were further tested through genotyping three additional validation cohorts followed by meta-analysis in all five cohorts totaling 3,132 cases and 3,317 controls. Twelve SNPs had evidence of association in the GWAS (P<0.0071), were directionally consistent in the Replication cohort and were associated with T2DM in subjects without nephropathy (P<0.05). Meta-analysis in all cases and controls revealed a single SNP reaching genome-wide significance (P<2.5×10(-8)). SNP rs7560163 (P = 7.0×10(-9), OR (95% CI) = 0.75 (0.67-0.84)) is located intergenically between RND3 and RBM43. Four additional loci (rs7542900, rs4659485, rs2722769 and rs7107217) were associated with T2DM (P<0.05) and reached more nominal levels of significance (P<2.5×10(-5)) in the overall analysis and may represent novel loci that contribute to T2DM. We have identified novel T2DM-susceptibility variants in the African-American population. Notably, T2DM risk was associated with the major allele and implies an interesting genetic architecture in this population. These results suggest that multiple loci underlie T2DM susceptibility in the African-American population and that these loci are distinct from those identified in other ethnic populations.

Twelve type 2 diabetes susceptibility loci identified through large-scale association analysis

By combining genome-wide association data from 8,130 individuals with type 2 diabetes (T2D) and 38,987 controls of European descent and following up previously unidentified meta-analysis signals in a further 34,412 cases and 59,925 controls, we identified 12 new T2D association signals with combined P<5x10(-8). These include a second independent signal at the KCNQ1 locus; the first report, to our knowledge, of an X-chromosomal association (near DUSP9); and a further instance of overlap between loci implicated in monogenic and multifactorial forms of diabetes (at HNF1A). The identified loci affect both beta-cell function and insulin action, and, overall, T2D association signals show evidence of enrichment for genes involved in cell cycle regulation. We also show that a high proportion of T2D susceptibility loci harbor independent association signals influencing apparently unrelated complex traits.

Integrated detection and population-genetic analysis of SNPs and copy number variation

Dissecting the genetic basis of disease risk requires measuring all forms of genetic variation, including SNPs and copy number variants (CNVs), and is enabled by accurate maps of their locations, frequencies and population-genetic properties. We designed a hybrid genotyping array (Affymetrix SNP 6.0) to simultaneously measure 906,600 SNPs and copy number at 1.8 million genomic locations. By characterizing 270 HapMap samples, we developed a map of human CNV (at 2-kb breakpoint resolution) informed by integer genotypes for 1,320 copy number polymorphisms (CNPs) that segregate at an allele frequency >1%. More than 80% of the sequence in previously reported CNV regions fell outside our estimated CNV boundaries, indicating that large (>100 kb) CNVs affect much less of the genome than initially reported. Approximately 80% of observed copy number differences between pairs of individuals were due to common CNPs with an allele frequency >5%, and more than 99% derived from inheritance rather than new mutation. Most common, diallelic CNPs were in strong linkage disequilibrium with SNPs, and most low-frequency CNVs segregated on specific SNP haplotypes.

Joint-specific hand symptoms and self-reported and performance-based functional status in African Americans and Caucasians: The Johnston County Osteoarthritis Project

OBJECTIVE

To assess associations between joint-specific hand symptoms and self-reported and performance-based functional status.

METHODS

Participants were from the population-based Johnston County Osteoarthritis Project. Symptoms in the distal interphalangeal (DIP), proximal interphalangeal (PIP), first carpometacarpal (CMC), and metacarpophalangeal (MCP) joints were assessed on a 30-joint diagram of both hands. Self-reported function was assessed by Health Assessment Questionnaire (HAQ) and performance-based function by timed repeated chair stands and 8-foot walk time. Separate multiple logistic regression models examined associations between symptoms in specific hand joint groups, symptoms in >/=2 hand joint groups and number of symptomatic hand joints, and functional status measures, controlling for age, race/ethnicity, sex, body mass index, radiographic knee and hip OA, knee and hip symptoms and depressive symptoms.

RESULTS

Those with symptomatic hand joint groups were more likely than those without these complaints to report more difficulty and require longer times for performance measures. Those with 2 or more symptomatic hand joint groups were more likely to have higher HAQ scores (OR = 1.97 (1.53 to 2.53)) and require more time to complete 5 chair stands (OR = 1.98 (1.23 to 3.18)) and the 8 foot walk test (OR = 1.49 (1.12 to 1.99)).

CONCLUSIONS

Joint-specific hand symptoms are associated with difficulty performing upper- or lower-extremity tasks, independent of knee and hip OA and symptoms, suggesting that studies examining functional status in OA should not ignore symptomatic joints beyond the joint site of interest, even when functional measures appear to be specific for the joint site under study.

Diurnal variation of serum and urine biomarkers in patients with radiographic knee osteoarthritis

OBJECTIVE

To evaluate diurnal variation of biomarkers in subjects with osteoarthritis (OA) of the knee.

METHODS

Twenty subjects with radiographic knee OA were admitted to the General Clinical Research Center of Duke University for an overnight stay to undergo serial blood and urine sampling. Biomarkers measured included serum hyaluronan (HA), cartilage oligomeric matrix protein (COMP), keratan sulfate (KS-5D4), aggrecan neoepitope (CS846), high-sensitivity C-reactive protein (hsCRP), osteocalcin, transforming growth factor beta1 (TGFbeta1), and type II collagen (CII)-related epitopes (neoepitope from cleavage of CII [C2C], carboxy-terminus of three-quarter peptide from cleavage of CI and CII [C1,2C], and type II procollagen carboxy-propeptide [CPII] in serum, and C-terminal telopeptides of CII [CTX-II] and C2C in urine).

RESULTS

Levels of serum HA, COMP, KS-5D4, and TGFbeta1 increased significantly from T0 (before arising from bed) to T1 (1 hour after arising). More diurnal variation in HA was observed in patients with higher daily mean HA concentrations. CPII increased significantly from T0 to T2 (4 hours after arising). Urinary concentrations of CTX-II were also found to vary with morning activity, decreasing significantly from T0 to T2. Urinary C2C concentrations increased significantly from T0 until T3 (early evening). No diurnal variations in CS846, hsCRP, osteocalcin, serum C2C, or C1,2C were observed. Six biomarkers (serum C2C, C1,2C, COMP, KS-5D4, TGFbeta1, and urinary CTX-II) were associated with radiographic knee OA (expressed as the sum of Kellgren/Lawrence radiographic severity grades), with the strongest correlations observed with measurements obtained at later time points (either T2 or T3).

CONCLUSION

Our study results suggest that serum and urine sampling for HA, COMP, KS-5D4, TGFbeta1, CPII, urinary CTX-II, and urinary C2C should be standardized in future OA clinical trials. Serum and urine sampling at late midday time points may be the optimal approach for OA studies, although this result should be validated in a larger cohort.

Fourier Transform Emission Spectroscopy of the Visible Transitions of AuCl

The visible electronic transitions of AuCl were observed at high resolution for the first time. The spectrum was recorded with the Fourier transform spectrometer associated with the McMath-Pierce solar telescope at Kitt Peak. The excited AuCl molecules were produced in a microwave discharge, with 4 Torr of helium seeded with 3% chlorine flowing over AuCl3 powder. Constants for the X1Sigma+, AOmega = 1, and BOmega = 0(+) states of Au35Cl are presented. The AOmega = 1 and the BOmega = 0(+) states may be two spin-orbit components of a 3Pi electronic state, and molecular parameters for this excited 3Pi state also are given. Copyright 1999 Academic Press.

The effect of real and simulated time-zone shifts upon the circadian rhythms of body temperature, plasma 11-hydroxycorticosteroids, and renal excretion in human subjects

1. Observations were made upon five subjects who flew through 4(1/2)-6 time zones, four of them returning later to their starting point, and upon twenty-three subjects experiencing simulated 6 or 8 hr time zones shifts in either direction in an isolation unit.2. Measurements were made of plasma concentration of 11-hydroxycorticosteroids, of body temperature, and of urinary excretion of sodium, potassium and chloride. Their rhythm was defined, where possible, by fitting a sine curve of period 24 hr to each separate 24-hr stretch of data and computing the acrophase, or maximum predicted by the sine curve.3. The adaptation of the plasma steroid rhythm was assessed by the presence of a sharp fall in concentration after the sample collected around 08.00 hr. The time course of adaptation varied widely between individuals; it was usually largely complete by the fourth day after westward, and rather later after eastward, flights. After time shift the pattern often corresponded neither to an adapted nor to an unadapted one, and in a subject followed for many months after a real flight a normal amplitude only appeared 2-3 months after flight.4. Temperature rhythm adapted by a movement of the acrophase, without change in amplitude, although on some days no rhythm could be observed. This movement was always substantial even on the first day, and was usually nearly complete by the fifth.5. High nocturnal excretion of electrolyte was often seen in the early days after time shift, more notably after simulated westward flights. Adaptation of urinary electrolyte rhythms usually proceeded as with temperature, but the movement of the acrophase was slower, more variable between individuals, more erratic, and sometimes reversed after partial adaptation. On a few days there were two maxima corresponding to those expected on real and on experimental time.6. Sodium excretion was much less regular than that of potassium, but adapted more rapidly to time shift, so that the two often became completely dissociated. Chloride behaved much as sodium.7. The time course of adaptation of the plasma steroid and urinary potassium rhythms were sufficiently similar to suggest a causal connexion. The time course of adaptation of the temperature rhythm did not coincide with that of any other component considered here.

Circadian excretory rhythms in night workers

Conroy, R. T. W. L., Elliott, A. L., and Mills, J. N. (1970).Brit. J. industr. Med.,27, 356-363. Circadian excretory rhythms in night workers. Urine samples have been collected from day and night shift workers in a light engineering factory over periods of 24 or 48 hours during which blood was also collected for determination of plasma 11-hydroxycorticosteroids (11-OHCS). Different subjects divided their 24-hour output into as few as 4 or as many as 14 portions. Where possible, the timing of the excretory rhythms was assessed objectively by fitting a sine curve. The potassium excretory rhythm was, in most subjects, well adapted to night work in that they excreted least during their hours of sleep; no relationship could be discerned between potassium excretory and plasma 11-OHCS rhythms. The sodium excretory rhythm was less regular than that of potassium in both night and day workers, and in night workers both sodium excretion and urine flow were often high during the hours of sleep, so that the subjects were sometimes awakened by the need to micturate. There was, however, sufficient association between the behaviour of sodium and potassium to suggest that their excretory rhythms have a common cause, and that this is not the secretion of 11-OHCS. Phosphate excretion fell sometimes on rising, even though plasma 11-OHCS concentration was not high, and sometimes after a high level of plasma 11-OHCS, at a time other than on rising. This suggests that these are two independent contributory causes of the usual morning fall in phosphate excretion.

Circadian rhythms in plasma concentration of 11-hydroxycorticosteroids in men working on night shift and in permanent night workers

Conroy, R. T. W. L., Elliott, Ann L., and Mills, J. N. (1970).Brit. J. industr. Med.,27, 170-174. Circadian rhythms in plasma concentration of 11-hydroxycorticosteroids in men working on night shift and in permanent night workers. Blood samples have been collected for estimation of plasma 11-hydroxycorticosteroids from three groups of workers - day and night shift workers in a light engineering factory, and night workers in a newspaper printing works. Up to five samples were collected over 24 hr, or two samples per 24 hr were collected for three days. In conformity with the observations of others, day workers showed maximal concentrations in the morning around the time when they started work. In the newspaper workers maximal concentrations were found when they awoke around 14·00 hr. Night shift workers in the engineering works showed a greater variety of pattern, some showing the pattern usual in a day worker, some showing a maximum concentration about midnight and a minimum around 06·00 hr and a large proportion showing no clear circadian rhythm. In the newspaper workers the rhythm was thus well adapted to their pattern of nocturnal work, whereas relatively few of the night shift workers in the engineering works showed such adaptation. It appears that the adrenal cortical rhythm can be adapted to night work in a community in which this is universal, accepted and lifelong, but that such adjustment is unusual in men on night shift work for limited periods, and whose associates are mainly following a usual nycthemeral existence.