The effect of oral statin therapy on strabismus in patients with thyroid eye disease

Statins and thyroid eye disease (TED): a systematic review

PURPOSE

Thyroid eye disease (TED) is the foremost extrathyroidal manifestation of Graves' disease (GD). Currently, available treatments do not entirely prevent the long-term consequences of TED and have distinct disadvantages. Therefore, this systematic review explored available evidence regarding the efficacy of statins in preventing and treating TED.

METHODS

Relevant studies investigating statin usage in patients with GD or TED were identified by searching Medline (Pubmed and Ovid), Scopus, Web of Science, ProQuest, and Cochrane Library databases (from the database inception to September 2023). The review was done according to the PRISMA statement. Web searching was done independently by two investigators. Two researchers independently extracted the data, and any disagreement was adjudicated by consensus. Based on the study design, the studies' quality appraisal was done using the Newcastle-Ottawa Scale (NOS) and Version 2 of the Cochrane risk-of-bias tool (RoB2).

RESULTS

The literature search identified 145 publications, of which four met the inclusion criteria (Three retrospective cohort studies and one randomized clinical trial) and were reviewed in full text. The two retrospective cohort studies demonstrated the beneficial effects of statins on TED in newly diagnosed GD Stein et al. showed that statins, regardless of the type, prevent or delay TED (HR: 0.74 (0.65-0.84)), especially in men or treatment duration of more than one year. Nilsson et al. fascinatingly revealed that at least 60 days of statin usage in the preceding year could decrease the risk of TED development by around 40%. One RCT showed a higher treatment response for active moderate-to-severe TED in patients with hypercholesterolemia who took atorvastatin 20 mg in addition to ivGC for 24 weeks without any increase in serious side effects. The retrospective study revealed that the need for reconstructive surgery was reduced in patients with severe TED who received statin therapy.

CONCLUSION

Statin therapy could be a potential adjunctive modality for preventing and treating TED.

TRIAL REGISTRATION

PROSPERO registration number: CRD42022315522.

Dysthyroid Optic Neuropathy

PURPOSE

Dysthyroid optic neuropathy (DON) is a sight-threatening complication of thyroid eye disease (TED). This review provides an overview of the epidemiology, pathogenesis, diagnosis, and current therapeutic options for DON.

METHODS

A literature review.

RESULTS

DON occurs in about 5% to 8% of TED patients. Compression of the optic nerve at the apex is the most widely accepted pathogenic mechanism. Excessive stretching of the nerve might play a role in a minority of cases. Increasing age, male gender, smoking, and diabetes mellitus have been identified as risk factors. Diagnosis of DON is based on a combination of ≥2 clinical findings, including decreased visual acuity, decreased color vision, relative afferent pupillary defect, visual field defects, or optic disc edema. Orbital imaging supports the diagnosis by confirming apical crowding or optic nerve stretching. DON should be promptly treated with high-dose intravenous glucocorticoids. Decompression surgery should be performed, but the response is incomplete. Radiotherapy might play a role in the prevention of DON development and may delay or avoid the need for surgery. The advent of new biologic-targeted agents provides an exciting new array of therapeutic options, though more research is needed to clarify the role of these medications in the management of DON.

CONCLUSIONS

Even with appropriate management, DON can result in irreversible loss of visual function. Prompt diagnosis and management are pivotal and require a multidisciplinary approach. Methylprednisolone infusions still represent first-line therapy, and surgical decompression is performed in cases of treatment failure. Biologics may play a role in the future.

Statin use and the reoperation rates in glaucoma filtration surgery - population-based cohort study

PURPOSE

To examine the association of systemic statin therapy and reoperation rate after glaucoma filtration surgery (GFS).

METHODS

This is a population-based, historic cohort study of 2705 eyes undergoing GFS in Finland between July 2009 and December 2016. GFSs were identified from national administrative healthcare registers. Baseline sociodemographic and health characteristics were documented. Reoperation rates of GFS subgroups were analysed, with statin users compared to non-users. The outcomes were modelled using a Poisson regression model adjusted for age, sex, education, statin use, chronic comorbidities, and cataract surgery with incident rate ratios (IRR) as the main outcome measure.

RESULTS

The cohort contained 2263 subjects with open-angle glaucoma (OAG), 823 men and 1440 women. Surgery was performed on 2705 eyes. First documented procedures: deep sclerectomy (DS) (n = 1601), trabeculectomy (TRE) (799) and glaucoma drainage device (GDD) implantation (305) respectively. In total, 438 secondary operations were performed during the 7.5-year (median 2.25 years) follow-up period. The reoperation rates were 19% after DS, 12% after TRE, and 13% after GDD. Of the surgical procedures, 32% were performed on eyes of patients receiving statin therapy. Statin users showed no difference in reoperation rates (IRR 1.06, CI 0.82-1.37). In subgroups, no difference was observed in the reoperation rates adjusted with statin use after filtration surgery (DS, TRE) (IRR 1.06, CI 0.8-1.40) or GDD implantation (0.57, CI 0.20-1.63).

CONCLUSION

Systemic statin therapy among surgically treated OAG patients had no impact on secondary surgery rates following DS, TRE or GDD implantation.

Statins for Graves' orbitopathy (STAGO): a phase 2, open-label, adaptive, single centre, randomised clinical trial

BACKGROUND

A protective action of statins on development of Graves' orbitopathy suggests that statins might be used for treatment of the disease. We aimed to assess the efficacy of the addition of a statin, atorvastatin, to intravenous glucocorticoids (ivGCs) on Graves' orbitopathy outcomes in patients with hypercholesterolaemia.

METHODS

We did a randomised, open-label, phase 2, adaptive, clinical trial at a single, tertiary, referral hospital in Pisa, Italy. Patients with moderate-to-severe, active Graves' orbitopathy, with a low-density lipoprotein cholesterol concentration between 2·97 and 4·88 mmol/L were eligible for inclusion. Patients were randomly assigned (1:1) in 11 blocks of eight, using a computer-based system, to the ST group or the NST group. The ST group received ivGCs (methylprednisolone 500 mg once a week for 6 weeks followed by 250 mg once a week for an additional six weeks) for 12 weeks and oral atorvastatin (20 mg once a day) for 24 weeks. The NST group only received the ivGC regimen. Patients were unmasked to group allocation; however, the ophthalmological investigator was masked to randomisation. The primary endpoint was the Graves' orbitopathy outcome (composite evaluation of exophthalmos, clinical activity score, eyelid aperture, and diplopia) at 24 weeks in the modified intention-to-treat (ITT) population (patients who attended the week 12 visit). Patients were considered responders when at least two of the following criteria were fulfilled in the most affected eye, without worsening in any of the same measures in both eyes: (1) reduction in exophthalmos of 2 mm or more, with no increase by 2 mm or more in the other eye; (2) reduction of clinical activity score by two or more points; (3) reduction in eyelid aperture by 2 mm or more, with no increase by 2 mm or more in the other eye; and (4) disappearance or improvement (change from constant to inconstant, intermittent, or absent, or from inconstant to intermittent or absent) of diplopia, and (5) improvement in visual acuity by 0·2 decimals or more. The trial is registered with EUDRACT, 2018-001317-33, and ClinicalTrials.gov, NCT03110848.

FINDINGS

Between June 1, 2020, and Nov 30, 2020, 119 patients were screened for inclusion, of whom 88 (74%) patients were enrolled and randomly assigned to one of the two treatment groups (44 [50%] to the ST group and 44 [50%] to the NST group). Eight (9%) patients did not attend the 12 week visit; 80 (91%) patients (18 [23%] men and 62 [78%] women) were included in the modified ITT population (41 [51%] in the ST group and 39 [49%] in the NST group]. The proportion of Graves' orbitopathy composite evaluation responders at 24 weeks was higher in the ST group (21 [51%] of 41 patients) than the NST group (11 [28%] of 39 patients; attributable risk 0·23 [95% CI 0·02-0·44]; p=0·042). 26 adverse events occurred in 21 (24%) of 88 patients in the safety population. One (2%) of 44 patients in each group required treatment discontinuation, with no serious adverse events and no difference between groups.

INTERPRETATION

Addition of oral atorvastatin to an ivGC regimen improved Graves' orbitopathy outcomes in patients with moderate-to-severe, active eye disease who were hypercholesterolaemic. Future phase 3 studies, which could potentially recruit patients regardless of low-density lipoprotein cholesterol concentration, are required to confirm this association.

FUNDING

Associazione Allievi Endocrinologia Pisana.

Current Knowledge on Graves' Orbitopathy

(1) Background: Graves' orbitopathy (GO) is an autoimmune inflammation of the orbital tissues and the most common extra-thyroid symptom of Graves' disease (GD). Mild cases of GO are often misdiagnosed, which prolongs the diagnostic and therapeutic process, leading to exacerbation of the disease. A severe course of GO may cause permanent vision loss. (2) Methods: The article presents an analysis of GO-its etiopathogenesis, diagnostics, current treatment and potential future therapeutic options based on a review of the currently available literature of the subject. (3) Results: Current treatment of the active GO consists predominantly in intravenous glucocorticoids (GCs) administration in combination with orbital radiotherapy. The growing knowledge on the pathogenesis of the disease has contributed to multiple trials of the use of immunosuppressive drugs and monoclonal antibodies which may be potentially effective in the treatment of GO. Immunosuppressive treatment is not effective in patients in whom a chronic inflammatory process has caused fibrous changes in the orbits. In such cases surgical treatment is performed-including orbital decompression, adipose tissue removal, oculomotor muscle surgery, eyelid alignment and blepharoplasty. (4) Conclusions: Management of GO is difficult and requires interdisciplinary cooperation in endocrinology; ophthalmology, radiation oncology and surgery. The possibilities of undertaking a reliable assessment and comparison of the efficacy and safety of the therapeutic strategies are limited due to the heterogeneity of the available studies conducted mostly on small group of patients, with no comparison with classic systemic steroid therapy. The registration by FDA of Teprotumumab, an IGF1-R antagonist, in January 2020 may be a milestone in future management of active GO. However, many clinical questions require to be investigated first.

Update on the clinical assessment and management of thyroid eye disease

PURPOSE OF REVIEW

To offer an update on advances and controversies in the assessment, investigation and treatment of thyroid eye disease (TED), a disfiguring orbital autoimmune disease, which can manifest with diplopia and threaten not only sight - but also life.

RECENT FINDINGS

Developments in biomarkers and imaging are helping to tailor the management of patients. Emerging therapies target different pathways in the disease and are informed by studies into TED pathogenesis: the last 2 years has, for example, seen the culmination of a two-decade long bench-to-bedside story in which an original focus on the IGF1 receptor has translated into an effective treatment for proptosis in thyroid eye disease. Whether this will result in a real-world reduction in TED-related morbidity will depend on access; commercial pricing decisions may preclude widespread adoption of novel therapies.

SUMMARY

Thyroid eye disease research is enjoying a renaissance with advances in both monitoring and treatment coupled with a renewed emphasis on a holisitic approach, which includes aesthetic care for patients; this is perhaps the most exciting time to be part of the international thyroid eye disease community in decades - for physicians, surgeons and patients. The commercial window for break-through drugs are narrowing with an array of new therapeutic agents in the pipeline over the coming decade.