Statin Adverse Events in Primary Prevention: Between Randomized Trials and Observational Studies

Umbrella review of 42 systematic reviews with meta-analyses: the safety of proton pump inhibitors

BACKGROUND

Proton pump inhibitors (PPIs) are widely used to treat and prevent acid-related disorders. Despite high efficacy, PPI safety has been increasingly scrutinised. However, no comprehensive review summarising investigations of various adverse events is available.

AIMS

To perform an umbrella review to comprehensively assess associations between adverse events and PPI use.

METHODS

In accordance with PRISMA, an umbrella review of systematic reviews with meta-analyses was conducted. PubMed and EMBASE were searched from 2015 to July 2019. AMSTAR 2 and GRADE were used to assess quality and certainty of evidence. Author-reported quality assessments were also reviewed.

RESULTS

Forty-two systematic reviews with meta-analyses, supported predominantly by observational evidence, were included. The most comprehensive studies reported statistically significant associations with PPI use for several outcomes, including: fractures (eg, hip; RR = 1.20; 95% CI = 1.14-1.28; n = 2 103 800), kidney disease (eg, acute kidney injury; RR = 1.61; 95% CI = 1.16-2.22; n = 2 396 640), infections (eg, Clostridioides difficile; OR = 1.99; 95% CI = 1.73-2.30; n = 356 683), gastric cancer (OR = 2.50; 95% CI = 1.74-3.85; n = 943 070) and gastrointestinal events (eg, fundic gland polyps; OR = 2.46; 95% CI = 1.42-4.27; n = 40 218). No associations with non-gastric cancers, or neurological disease were concluded, with conflicting evidence for cardiovascular outcomes. Certainty based on GRADE was very low for most outcomes.

CONCLUSIONS

This review identified several published associations between PPIs and adverse outcomes, however, further investigation is needed to understand their clinical significance and the likelihood of causal relationship. If higher quality evidence is generated substantiating the potential risks, it may be necessary for clinicians to consider alternative treatment strategies, especially when PPI efficacy is suboptimal.

Influence of statin-potency on the risk of kidney disease - A nationwide cohort study using laboratory data

PURPOSE

To estimate the risk of kidney disease in high-potency statin users compared to those treated with low-potency statins without history of kidney disease at statin initiation, linking the Swedish national healthcare registers and laboratory data.

METHODS

Incident users of statins, ≥40 years of age, with estimated Glomerular Filtration Rate (eGFR) >60 ml/min/1.73 m² and no diagnosis of kidney disease at treatment initiation were identified between 2006 and 2007 and then followed for 2-years. The outcome was the incidence of kidney disease identified by the presence of the diagnostic code in the healthcare registers or eGFR <60 ml/min/1.73 m² . We estimated hazard ratios (HRs) and 95% confidence intervals (CIs) with adjusted and propensity score (PS)-matched Cox proportional hazards models.

RESULTS

A total of 27 385 patients were identified, 25.2% of which treated with a high-potency statin. During the follow-up, 68 (0.25%) patients were identified with a diagnosis of kidney disease from the registers. The number increased to 2498 (9.1%) when the criteria of eGFR <60 ml/min/1.73 m² was added. The adjusted HR of kidney disease in high-potency statin users was 1.14 (95%CI 1.03-1.25) compared to low-potency users; the result was unchanged after the PS approach.

CONCLUSIONS

Adding information from laboratory data to those from the national health registers, a slightly increased risk for kidney disease was found in high-potency statin users without pre-existing kidney disease at treatment initiation compared to those treated with low-potency statins.

Statin use and medically attended acute respiratory illness among influenza vaccine recipients

BACKGROUND

Previous studies have suggested that statins decrease influenza vaccine effectiveness and increase risk of medically attended acute respiratory illness (MAARI).

OBJECTIVES

To examine the association of incident statin use and MAARI in a cohort of influenza vaccine recipients.

METHODS

This retrospective cohort study evaluated influenza vaccine recipients within the Tricare population. The primary outcome compared MAARI incidence during the follow-up period in a propensity score-matched cohort of incident statin users and statin non-users. Secondary analysis included propensity score-adjusted comparisons between incident statin users and statin non-users in the entire cohort and prespecified sub-cohorts with and without comorbidities. The propensity score was derived from 72 variables encompassing demographics, medical history, comorbidities, medication use, and healthcare utilization.

RESULTS

MAARI incidence in statin users was similar to non-users in the propensity score-matched cohort (odds ratio [OR] 0.92; 95% confidence interval [CI] 0.84-1.01). In contrast, statin users with lower comorbidity had lower OR for MAARI compared to non-users (Charlson Score zero cohort: 0.85 [CI 0.74-0.98]; No Diabetes cohort: 0.88 [CI 0.80-0.96]).

CONCLUSION

Incident statin use was not associated with increased MAARI incidence and may be associated with lower incidence of MAARI in those with less comorbidity. This study thus offers reassurance regarding the effectiveness of the influenza vaccine in statin users.

Association of Statin Use with Increased Risk of Musculoskeletal Conditions: A Retrospective Cohort Study

INTRODUCTION

Musculoskeletal conditions, including osteoarthritis (OA), result in tremendous disability and cost. Statins are among the most commonly prescribed medications and their use for primary prevention in many otherwise healthy individuals, including those who are physically active, is increasing. There is conflicting evidence regarding the relationship of statin use and musculoskeletal conditions. Given the rising disability associated with musculoskeletal conditions, understanding predisposing factors, including medication-related exposures, deserves further attention.

OBJECTIVES

We examined the association between statin use and the risk of being diagnosed with non-traumatic arthropathies, use-related injury, and undergoing rehabilitation in a cohort with longitudinal follow-up.

METHODS

Patients enrolled in a regional military healthcare system between 2003 and 2012 were evaluated in this retrospective cohort study. A propensity score was generated to match statin-users and nonusers using 115 baseline characteristics. Outcomes included ICD-9 diagnoses codes for Agency for Healthcare Research and Quality disease categories of: non-traumatic arthropathies, use-related injury and undergoing rehabilitation. Primary analysis examined the outcomes in statin-users and nonusers after propensity score matching using conditional logistic regression analysis.

RESULTS

Initially, 60,455 patients were identified. We propensity score-matched 6728 statin users with 6728 nonusers (52 years of age, ~ 47% women). In the propensity score-matched cohort, non-traumatic arthropathies occurred in 59.8% of statin users and 56.0% of nonusers [odds ratio (OR) 1.17, 95% confidence interval (95% CI) 1.09-1.25] and use related injury occurred in 31.9% of statin users and 29.8% of nonusers (OR 1.11, 95% CI 1.03-1.19). There was no difference between statin users and nonusers undergoing rehabilitation (22.6% among statin users, 21.9% among nonusers, OR 1.04, 95% CI 0.96-1.13).

CONCLUSION

Statin use was associated with a significant increased risk of non-traumatic arthropathies and use-related injury. Our results provide additional data that can inform patient and clinician conversations about the benefits and risks of statin use.

Real-world crude incidence of hypoglycemia in adults with diabetes: Results of the InHypo-DM Study, Canada

OBJECTIVE

Very few real-world studies have been conducted to assess the incidence of diabetes-related hypoglycemia. Moreover, there is a paucity of studies that have investigated hypoglycemia among people taking secretagogues as a monotherapy or in combination with insulin. Accordingly, our research team developed and validated the InHypo-DM Person with Diabetes Mellitus Questionnaire (InHypo-DMPQ) with the aim of capturing the real-world incidence of self-reported, symptomatic hypoglycemia. The questionnaire was administered online to a national sample of Canadians (≥18 years old) with type 1 diabetes mellitus (T1DM) or type 2 diabetes mellitus (T2DM) treated with insulin and/or insulin secretagogues.

RESEARCH DESIGN AND METHODS

Self-report data obtained from the InHypo-DMPQ were descriptively analyzed to ascertain the crude incidence proportions and annualized incidence densities (rates) of 30-day retrospective non-severe and 1-year retrospective severe hypoglycemia, including daytime and nocturnal events.

RESULTS

A total of 552 people (T2DM: 83%; T1DM: 17%) completed the questionnaire. Over half (65.2%) of the total respondents reported experiencing at least one event (non-severe or severe) at an annualized crude incidence density of 35.1 events per person-year. The incidence proportion and rate of non-severe events were higher among people with T1DM versus T2DM (77% and 55.7 events per person-year vs 54% and 28.0 events per person-year). Severe hypoglycemia was reported by 41.8% of all respondents, at an average rate of 2.5 events per person-year.

CONCLUSIONS

The results of the InHypo-DMPQ, the largest real-world investigation of hypoglycemia epidemiology in Canada, suggest that the incidence of hypoglycemia among adults with diabetes taking insulin and/or insulin secretagogues is higher than previously thought.

Statin initiations and QRISK2 scoring in UK general practice: a THIN database study

BACKGROUND

Statin prescribing should be based on cardiovascular disease (CVD) risk, but evidence suggests overtreatment of low-risk groups and undertreatment of high-risk groups.

AIM

To investigate the relationship between CVD risk scoring in primary care and initiation of statins for the primary prevention of CVD, and the effect of changes to the National Institute for Health and Care Excellence (NICE) guidance in 2014.

DESIGN AND SETTING

Historical cohort study using UK electronic primary care records.

METHOD

A cohort was created of statin-naïve patients without CVD between 1 January 2000 and 31 December 2015. CVD risk scores (calculated using QRISK2 available from 2012) and statin initiations were identified. Rates of CVD risk score recording were calculated and relationships between CVD risk category (low-, intermediate-, and high-risk: <10%, 10-19.9%, and ≥20% 10-year CVD risk) and statin initiation were analysed.

RESULTS

A total of 1.4 million patients were identified from 248 practices. Of these, 151 788 had a recorded CVD risk score since 2012 (10.67%) and 217 860 were initiated on a statin (15.31%). Among patients initiated on a statin after 2012, 27.1% had a documented QRISK2 score: 2.7% of low-risk, 13.8% of intermediate-risk, and 35.0% of high-risk patients were initiated on statins. Statin initiation rates halved from a peak in 2006. After the 2014 NICE guidelines, statin initiation rates declined in high-risk patients but increased in intermediate-risk patients.

CONCLUSION

Most patients initiated on statins had no QRISK2 score recorded. Most patients at high risk of CVD were not initiated on statins. One in six statin initiations were to low-risk patients indicating significant overtreatment. Initiations of statins in intermediate-risk patients rose after NICE guidelines were updated in 2014.

Statin Use and the Risk of Cataracts: A Systematic Review and Meta-Analysis

BACKGROUND

Cataracts are the main cause of poor vision and blindness worldwide. The effects of statin administration on cataracts remain debated. Therefore, we conducted a systematic review and meta-analysis to determine whether statin use affects the risk of cataracts.

METHODS AND RESULTS

We performed a systematic search of the electronic databases PubMed, EMBASE, and the Cochrane Library through January 2016. Weighted averages were reported as relative risk values with 95% CIs. Statistical heterogeneity scores were assessed with the standard Cochran's Q test and the I² statistic. A total of 6 cohort studies, 6 case-control studies, and 5 randomized controlled trials, together involving more than 313 200 patients, were included in our study. The pooled estimates of cohort studies indicated that the use of statins moderately increases the risk of cataracts (relative risk, 1.13; 95% CI, 1.01-1.25). The pooled estimates of case-control studies (relative risk=1.10, 95% CI, 0.99-1.23) and randomized controlled trials (relative risk, 0.89; 95% CI, 0.72-1.10) indicated that the use of statins does not increase the risk of cataracts. The sensitivity analysis confirmed the stability of the results. Heterogeneity was found among the cohort and case-control studies.

CONCLUSIONS

Based on the present meta-analysis of these studies, we could only conclude that there is no clear evidence showing that statin use increases the risk of cataracts. The most likely case is that there is no association between statin use and cataracts. Because of the considerable benefits of statins in cardiovascular patients, this issue should not deter their use.

Statins in Primary Prevention: Uncertainties and Gaps in Randomized Trial Data

Randomized controlled trials (RCTs) have provided evidence of the usefulness of statin primary prevention in lowering cardiovascular morbidity and mortality, yet uncertainties and gaps remain. The objective of this article was to perform a narrative review of RCTs of statins for primary prevention and identify uncertainties and gaps resulting from the design of individual studies. Such knowledge is important for informed physician-patient decisions. A literature search was conducted for RCTs of statins in primary prevention that included >1000 general patients and clinical outcomes as a primary endpoint. A total of 11 RCTs were identified; target population baseline characteristics, outcomes measures, statistical methods, and limitations regarding follow-up were reported. RCTs of statins in primary prevention show consistent overall beneficial effects on cardiovascular morbidity and mortality. Caveats involve the characteristics of individual study populations since target populations often differ from what is currently considered primary prevention. Only middle aged and older populations were adequately represented in these RCTs; women were under-represented. Only one study included total mortality as the primary endpoint; all other RCTs used composite major adverse cardiac events as the primary endpoint, which occasionally included a hard outcome such as death and a soft outcome such as hospitalization for angina. The use of Cox proportional hazard analysis in RCTs poses some challenges, and intention-to-treat analysis may mask adverse events. An understanding of the deficiencies of individual RCTs of statins in primary prevention is important in creating a patient-specific therapeutic clinical decision and in tailoring future research.

Association of statins with diabetes mellitus and diabetic complications: role of confounders during follow-up

Studies have associated statin use with increased risk of diabetes and diabetic complications. These studies often ensure comparability of statin users and non-users at baseline; however, most studies neglect to consider confounders that occur during follow-up. Failure to consider these confounders, such as new medications or procedures, may result in identification of a spurious association between statins and outcomes. The objective of this study was to examine the association of statins with diabetes mellitus and diabetic complications; and to examine potential confounders during the follow-up period that might affect this relationship. We conducted a retrospective cohort study using Tricare data (from October 1, 2003 to March 31, 2012). We propensity score-matched statin users and non-users on 115 baseline characteristics before starting statins; these characteristics would be potentially associated with the use of statins or the outcomes of interest. Outcomes included the risk of diabetes mellitus and diabetic complications. Out of 60,455 patients (10,910 statin users and 49,545 non-users), we propensity score-matched 6728 statin users to 6728 non-users. Statin users had higher ORs for diabetes (OR 1.34, 95% CI 1.24 to 1.44) and diabetes with complications (OR 1.28, 95% CI 1.16 to 1.42). Adjustment for potential confounders that occurred during the follow-up period did not explain or diminish the association between statins and adverse outcomes. Statin users in comparison to similar non-users were more commonly diagnosed with diabetes and diabetic complications, even after adjustment for potential confounders that occurred during the follow-up period.

Metabolic syndrome is associated with muscle symptoms among statin users

BACKGROUND

Muscle symptoms have been associated with statin use, but the relationship of statin-associated muscle symptoms with metabolic syndrome (MS) has not been reported previously.

OBJECTIVE

To evaluate the relationships between MS and its individual components with statin-associated muscle symptoms.

METHODS

Data were analyzed from the Understanding Statin Use in America and Gaps in Education (USAGE) study. Modified criteria to define the MS were used based on self-reported survey data.

RESULTS

Among USAGE subjects, the MS was present in 1364 of 3992 men (34.2%) and in 1716 women of 6149 women (27.9%). Subjects with the MS were 19% more likely (P = .0002) to report new or worsening muscle symptoms while on a statin. Three MS criteria-increased BMI, elevated triglycerides (TG), and low high-density lipoprotein cholesterol (HDL-C)-were associated with increased odds of muscle symptoms, by 18%, 32%, and 28%, respectively (all P < .001). The presence of MS also predicted increased odds of having discontinued a statin due to muscle symptoms (13% higher, P = .043). Among criteria for the MS, elevated TG (38% higher odds, P < .0001) and low HDL-C (37% higher odds, P = .0003) were positively associated with statin discontinuation, whereas hypertension (13% lower odds, P = .019) and diabetes mellitus (12% lower odds, P = .036) were inversely associated.

CONCLUSION

USAGE participants with MS were more likely to report experiencing muscle symptoms while taking a statin and to have discontinued a statin due to muscle symptoms. This appears to be attributable mainly to associations of muscle symptoms with elevated TG and low HDL-C levels. Additional research is warranted to confirm and further investigate these associations.

Statin Use and the Risk of Kidney Disease With Long-Term Follow-Up (8.4-Year Study)

Few studies have examined long-term effects of statin therapy on kidney diseases. The objective of this study was to determine the association of statin use with incidence of acute and chronic kidney diseases after prolonged follow-up. In this retrospective cohort study, we analyzed data from the San Antonio area military health care system from October 2003 through March 2012. Statin users were propensity score matched to nonusers using 82 baseline characteristics including demographics, co-morbidities, medications, and health care utilization. Study outcomes were acute kidney injury, chronic kidney disease (CKD), and nephritis/nephrosis/renal sclerosis. Of the 43,438 subjects included, we propensity score matched 6,342 statin users with 6,342 nonusers. Statin users had greater odds of acute kidney injury (odds ratio [OR] 1.30, 95% confidence interval [CI] 1.14 to 1.48), CKD (OR 1.36, 95% CI 1.22 to 1.52), and nephritis/nephrosis/renal sclerosis (OR 1.35, 95% CI 1.05 to 1.73). In a subset of patients without co-morbidities, the association of statin use with CKD remained significant (OR 1.53, 95% CI 1.27 to 1.85). In a secondary analysis, adjusting for diseases/conditions that developed during follow-up weakened this association. In conclusion, statin use is associated with increased incidence of acute and chronic kidney disease. These findings are cautionary and suggest that long-term effects of statins in real-life patients may differ from shorter term effects in selected clinical trial populations.

Association of Statin Therapy and Risks of Cholelithiasis, Biliary Tract Diseases, and Gallbladder Procedures: Retrospective Cohort Analysis of a US Population

BACKGROUND

Gallstone disease is a leading cause of morbidity in Western countries and carries a high economic burden. Statin medications decrease hepatic cholesterol biosynthesis and may, therefore, lower the risk of cholesterol cholelithiasis by reducing the cholesterol concentration in the bile. Population-based evidence, however, is sparse.

OBJECTIVE

To assess the risk of gallbladder diseases among statin users compared with nonusers in an American patient cohort.

METHODS

We performed a retrospective cohort study of patients enrolled in the San Antonio Tricare health system using data between October 2003 and March 2012. We defined 2 groups: statin users (use for 90 days or greater) and nonusers (no prior statin). A propensity score based on 82 variables was generated to match statin users and nonusers 1:1. Outcomes included incidence of cholelithiasis, biliary tract diseases, and gallbladder procedures.

RESULTS

A total of 43 438 patients were identified; 13 626 (31.4%) were statin users, and 29 812 (68.6%) were nonusers. We matched 6342 pairs of statin users and nonusers based on propensity score. The odds ratios (ORs) in statin users in comparison to nonusers were similar for cholelithiasis (OR = 0.86; 95% CI = 0.73, 1.02), biliary tract disease (OR = 0.85; 95% CI = 0.67-1.08), and gall bladder procedures (OR = 0.85; 95% CI = 0.69, 1.04).

CONCLUSIONS

Statin use was not significantly associated with either an increased or decreased risk of cholelithiasis or gallbladder disease.