Increased risk of peripheral arterial disease after hip replacement: an 11-year retrospective population-based cohort study

Optimal combination periprosthetic vasculature visualization and metal artifact reduction by spectral computed tomography using virtual monoenergetic images in total hip arthroplasty

OBJECTIVES

To investigate the optimal parameters of spectral CT for preferably visualizing the periprosthetic vasculature and metal artifact reduction (MAR) in total hip arthroplasty (THA).

METHODS

A total of 34 THA of 30 patients were retrospectively included. Image reconstructions included conventional image (CI), CI combined with MAR (CIMAR), and virtual monoenergetic images (VMI) combined with MAR (VMIMAR) at 50-120 keV. The attenuation and standard deviation of the vessel and artifact, and the width of artifact were measured. Qualitative scoring was evaluated including the vascular contour, the extent of artifact, and overall diagnostic evaluation.

RESULTS

The attenuation, noise of the vessel and artifact, and the width of artifact decreased as the energy level increased (p < 0.001). The downtrend was relatively flat at 80-120 keV, and the vascular attenuation dropped to 200 HU at 90 keV. The qualitative rating of vascular contour was significantly higher at CIMAR (3.47) and VMIMAR 60-80 keV (2.82-3.65) compared with CI (2.03) (p ≤ 0.029), and the highest score occurred at 70 and 80 keV (3.65 and 3.56). The score of the extent of artifact was higher at VMIMAR 80 keV than CIMAR (3.53 VS 3.12, p = 0.003). The score of the overall diagnostic evaluation was higher at VMIMAR 70 and 80 keV (3.32 and 3.53, respectively) than CIMAR (3.12) (p ≤ 0.035).

CONCLUSION

Eighty kiloelectron volts on VMIMAR, providing satisfactorily reduced metal artifacts and improved vascular visualization, can be an optimal recommended parameter of spectrum CT for the assessment of periprosthetic vasculature in THA patients.

CRITICAL RELEVANCE STATEMENT

The metal artifact is gradually reducing with increasing energy level; however, the vascular visualization is worsening. The vascular visualization is terrible above 100 keV, while the vessel is disturbed by artifacts below 70 keV. The best performance is found at 80 keV.

KEY POINTS

• VMIMAR can provide both reduced metal artifacts and improved vascular visualization. • Eighty kiloelectron volts on VMIMAR performs best in vascular visualization of total hip arthroplasty patients. • Energy spectrum CT is recommended for routine use in patients with total hip arthroplasty.

Long-Term Exposures to Air Pollutants and Risk of Peripheral Arterial Occlusive Disease: A Nationwide Cohort Study in Taiwan

Air pollution is one of the most alarming environmental issues which causes multiple health hazards. An association between air pollution and cardiovascular diseases has been established through many prior studies. In this study, we aimed to evaluate the risk of long-term exposure to air pollution (PM2.5, CO, and NO2) and its association with the risk of developing peripheral arterial occlusive disease (PAOD). PAOD is a condition involving impairment of perfusion of blood in the distal parts of the aorta due to narrowing of the arteries (arterial stenosis) and has been reported as a risk factor for developing cardiovascular diseases. Furthermore, the risk of PAOD increases with age, and hence is a serious public health issue and a cause for concern, especially for an aging society such as Taiwan. Two national-scale databases from Taiwan, the national health insurance database (NHIRD) and the Taiwan air quality-monitoring database (TAQMD), were linked to conduct this cohort study between 2003 and 2013. Cox proportional hazards regression with time-dependent modeling was used to evaluate the hazard ratio (HR) for PAOD with respect to daily exposure to air pollutants. The concentrations of each of the pollutants of interest (PM2.5, NO2, and CO) were categorized into four categories according to the daily average concentration of air pollutants for every quarter of the year, Q1 to Q4 (Q4 = highest). The cumulative incidence of PAOD was examined by Kaplan-Meier analysis with two-tailed log-rank test. A total of 1,598 PAOD cases were identified during the 10-year follow-up period, along with 98,540 non-PAOD controls. In the multivariate analysis, after adjusting for age, gender, urbanization level, residential area, baseline comorbidities, and medications, the adjusted HRs were PM2.5 = 1.14 (95% CI 1.13-1.16), NO2 = 1.03 (95% CI 1.02-1.04), and CO = 2.35 (95% CI 1.95-2.84). Kaplan-Meier analysis showed that CO (P < 0.0001) and PM2.5 (P < 0.0001) concentrations were strongly and positively associated with the cumulative incidence of PAOD during the follow-up period. Findings from this study established that prolonged exposure to air pollutants CO and PM2.5 are significant factors that, among other well-known causes, may also play a potential role in PAOD pathogenesis.

Impact of comorbidity on the short- and medium-term risk of revision in total hip and knee arthroplasty

Background

The impact of comorbidity on the risk of revision in patients undergoing Total Knee arthroplasty (TKA) and Total Hip Arthroplasty (THA) is not currently well known. The aim of this study was to analyze the impact of comorbidity on the risk of revision in TKA and THA.

Methods

Patients recorded in the Catalan Arthroplasty Register (RACat) between 01/01/2005 and 31/12/2016 undergoing TKA (n = 49,701) and THA (n = 17,923) caused by osteoarthritis were included. As main explanatory factors, comorbidity burden was assessed by the Elixhauser index, categorized, and specific comorbidities from the index were taken into account. Descriptive analyses for comorbidity burden and specific conditions were done. Additionally, incidence at 1 and 5 years’ follow-up was calculated, and adjusted Competing Risks models were fitted.

Results

A higher incidence of revision was observed when the number of comorbidities was high, both at 1 and 5 years for THA, but only at 1 year for TKA. Of the specific conditions, only obesity was related to the incidence of revision at 1 year in both joints, and at 5 years in TKA. The risk of revision was related to deficiency anemia and liver diseases in TKA, while in THA, it was related to peripheral vascular disorders, metastatic cancer and psychoses.

Conclusions

Different conditions, depending on the joint, might be related to higher revision rates. This information could be relevant for clinical decision-making, patient-specific information and improving the results of both TKA and THA.

Risk of peripheral arterial occlusive disease in patients with rheumatoid arthritis

Rheumatoid arthritis (RA) is associated with atherosclerosis. However, the relationship between RA and peripheral arterial occlusive disease (PAOD) remains unclear. We used a national health insurance database to identify a cohort of 30,812 patients diagnosed with RA between 2000 and 2011. Each RA patient was frequency-matched according to age and sex with a patient without RA from a control cohort. A multivariate Cox proportional hazards model was used to analyse the adjusted risk of PAOD. The incidence of PAOD was 1.73-fold higher (95 % confidence interval [CI] = 1.57–1.91) in the RA cohort than in the non-RA cohort. The adjusted risk of PAOD was the highest in the patients with RA aged ≤ 49 years (hazard ratio [HR] = 3.39, 95 % CI = 2.66–4.32). Patients with RA and various comorbidities showed a significantly higher risk of PAOD (HR = 9.62, 95 % CI = 4.86–19.1) compared with control patients without comorbidity. The risk of PAOD increased during the first year of follow-up. In conclusion, patients with RA have an independently higher risk of PAOD compared with the general population. Patients with RA and various comorbidities and those at a young age and early stage of the disease have an increased risk of PAOD.

Erectile dysfunction and the risk of prostate cancer

Background

Prostate cancer (PCa) is the most commonly diagnosed malignancy and the third leading cause of cancer death among men in developed countries. Because some risk factors are common between erectile dysfunction (ED) and PCa, we investigated the association between ED and subsequent PCa.

Methods

This nationwide population-based cohort study used data from the Taiwan National Health Insurance Research Database for the period 2000–2010. We identified patients newly diagnosed with ED by using codes from the International Classification of Diseases, Ninth Revision, Clinical Modification.

Results

In total, 5858 and 23432 patients were enrolled in the ED and non-ED cohorts, respectively. After adjustment for age, sex, and comorbidities, the overall incidence densities of PCa were significantly higher in the ED cohort than in the non-ED cohort, with an adjusted hazard ratio (aHR) of 1.19. The age-specific relative risk of PCa was significantly higher for all age groups in the ED cohort than in the non-ED cohort. Compared with patients without ED, those with organic ED had a 1.27-fold higher risk of PCa.

Conclusion

ED is a harbinger of PCa in some men. Physicians should consider the possibility of occult PCa in patients with ED regardless of age and comorbidities.

Association of lower urinary tract syndrome with peripheral arterial occlusive disease

PURPOSE

To describe atherosclerosis may lead to chronic bladder ischemia, eventually resulting in lower urinary tract syndrome (LUTS), and peripheral arterial occlusive disease (PAOD). We investigated the association of LUTS with PAOD.

METHODS

This nationwide population-based cohort study was based on data from the Taiwan National Health Insurance Database from 2000 to 2010; follow-up lasted until the end of 2011. We identified patients with newly diagnosed LUTS by using International Classification of Diseases, Ninth Revision, Clinical Modification codes.

RESULTS

In total, 36,042 and 36,042 patients were enrolled in LUTS and non-LUTS cohorts, respectively. After adjustment for age, sex, and comorbidities, the risk of subsequent PAOD was 1.36-fold higher [95% confidence interval (CI) = 1.26-1.46] in the LUTS cohort than in the non-LUTS cohort. The adjusted risk of PAOD was the highest in patients with LUTS without any comorbidity [adjusted hazard ratio (aHR) = 1.93, 95% CI = 1.54-2.41]. The age-specific relative risk of PAOD was significantly higher in all age groups, particularly in those aged <49 years (aHR = 1.80, 95% CI = 1.39-2.34], in the LUTS cohort than in the non-LUTS cohort.

CONCLUSION

LUTS is a risk factor for PAOD. Physicians should consider the possibility of underlying PAOD in patients with LUTS aged <49 years and without cardiovascular comorbidities. Additional studies developing strategies for decreasing the risk of PAOD are warranted.

Increased Long-Term Cardiovascular Risk After Total Hip Arthroplasty: A Nationwide Cohort Study

Total hip arthroplasty is a common and important treatment for osteoarthritis patients. Long-term cardiovascular effects elicited by osteoarthritis or the implant itself remain unknown. The purpose of the present study was to determine if there is an increased risk of late cardiovascular mortality and morbidity after total hip arthroplasty surgery.A nationwide matched cohort study with data on 91,527 osteoarthritis patients operated on, obtained from the Swedish Hip Arthroplasty Register. A control cohort (n = 270,688) from the general Swedish population was matched 1:3 to each case by sex, age, and residence. Mean follow-up time was 10 years (range, 7-21).The exposure was presence of a hip replacement for more than 5 years. The primary outcome was cardiovascular mortality after 5 years. Secondary outcomes were total mortality and re-admissions due to cardiovascular events.During the first 5 to 9 years, the arthroplasty cohort had a lower cardiovascular mortality risk compared with the control cohort. However, the risk in the arthroplasty cohort increased over time and was higher than in controls after 8.8 years (95% confidence interval [CI] 7.0-10.5). Between 9 and 13 years postoperatively, the hazard ratio was 1.11 (95% CI 1.05-1.17). Arthroplasty patients were also more frequently admitted to hospital for cardiovascular reasons compared with controls, with a rate ratio of 1.08 (95% CI 1.06-1.11).Patients with surgically treated osteoarthritis of the hip have an increased risk of cardiovascular morbidity and mortality many years after the operation when compared with controls.

An Independent Risk of Gout on the Development of Deep Vein Thrombosis and Pulmonary Embolism: A Nationwide, Population-Based Cohort Study

Previous studies indicated that gout is a risk factor of cardiovascular diseases. This study aimed to determine if patients with gout have an increased risk of deep vein thrombosis (DVT) or pulmonary embolism (PE).We used the Longitudinal Health Insurance Database, a subset of the national insurance claim dataset, which enrolled 1 million Taiwanese to identify 57,981 patients with gout and 115,961 reference subjects matched by sex, age, and entry date of diagnosis. The risk of DVT and PE was analyzed using the Cox proportional hazards model.In this Taiwanese dataset observed from 2000 to 2010, we found the incidence of DVT was 5.26 per 10 person-years in the gout cohort, which was twofold higher than the incidence of 2.63 per 10 person-years in the reference cohort. After adjusting for age, sex, and 9 comorbidities, the hazard ratio (HR) of developing DVT was 1.66 (95% confidence interval [CI] = 1.37-2.01). Among patients with gout, the youngest age group had the highest increase in the risk of developing DVT (HR [95% CI] = 2.04 [1.24-3.37] for ages 20 to 49 years, 1.80 [1.28-2.51] for ages 50 to 64 years, and 1.45 [1.11-1.91] for ages ≥65 years). The incidence of PE was about one-fifth that of DVT in gout patients, but the effect of gout on the risk was similar (HR [95% CI] = 1.53 [1.01-2.29]).Our analysis confirmed that gout increased the risk of DVT and PE. Further exploration is needed in the future.

Risk of Peripheral Arterial Occlusive Disease in Patients With Systemic Lupus Erythematosus: A Nationwide Population-Based Cohort Study

Systemic lupus erythematosus (SLE) is associated with atherosclerosis, but the relationship between SLE and peripheral arterial occlusive disease (PAOD) remains unclear. We sought to investigate this relationship by comparing cardiovascular complications in patients with and without SLE.Data on patients from 2000 to 2011 were collected from the National Health Insurance Research Database of Taiwan. The SLE cohort was frequency-matched according to age, sex, and history of diabetes mellitus (DM) with patients without SLE (control cohort). We evaluated the risk of cardiovascular complications, including hypertension, DM, stroke, chronic obstructive pulmonary disease, heart failure, coronary artery disease, and hyperlipidemia.The study included 10,144 patients with SLE and 10,144 control patients. The incidence of PAOD was 9.39-fold higher (95% confidence interval [CI] = 7.70-11.15) in the SLE cohort than in the non-SLE cohort. Moreover, SLE was an independent risk factor for PAOD. The adjusted risk of PAOD was highest in patients with SLE who were aged ≤34 years (hazard ratio = 47.6, 95% CI = 26.8-84.4). The risk of PAOD was highest during the first year of follow-up and decreased over time.Patients with SLE exhibit a higher incidence and an independently higher risk of PAOD compared with the general population. The PAOD risk is markedly elevated in patients with SLE who are young and in whom the disease is at an early stage.