Oral pilocarpine for symptomatic relief of dry mouth and dry eyes in patients with Sjögrens syndrome

Characterization of cognitive dysfunction in Sjögren's syndrome patients

Sjögren's syndrome is an autoimmune disorder primarily affecting women, with decreased saliva and tear production as the principal characteristic. Cognitive, neurological, and psychiatric disorders also are associated with Sjögren's. The present study addressed the hypothesis that patients with Sjögren's syndrome differ significantly from matched controls in the prevalence and impact of a number of neuropsychiatric abnormalities. Sjögren's patients and controls (n = 37 per group) underwent medical and psychiatric evaluation, demographic assessments, quality of life and symptom evaluation, and extensive testing of cognitive function and memory. Patients and controls were closely matched for age, gender distribution, verbal IQ, marital status, educational level, employment status, and current/past medical or psychiatric history. On most subjective self-ratings, Sjögren's patients reported greater fatigue, impaired physical functioning, feeling depressed, and autonomic symptomatology compared to controls. Impaired memory was described mainly as loss of thought continuity in the midst of a task or activity. However, the majority of objective measures of cognition, psychomotor function, and memory showed minimal differences between groups. Sjögren's patients rate themselves as impaired on multiple ratings of emotional, cognitive, and physical function, but objective measures of cognition reveal fewer substantive differences between patients and matched controls. Sjögren's patients perceive deteriorated physical function over time, but they achieve a level of functioning comparable to controls despite the burden of their illness.

Immunopathogenesis of keratoconjunctivitis sicca in the dog

Keratoconjunctivitis sicca (KCS), more commonly known as dry eye, is an inflammatory condition of the ocular surface caused by a pathologic reduction in the aqueous component of the tear film. It is seen commonly in the dog and defined as a Schirmer tear test with a reading of less than 10 mm in one minute. While KCS may be caused by neurological disease or drug toxicity, most cases are immune-mediated. Whereas the immunological basis of autoimmune KCS has been extensively investigated in humans and experimental rodent models, little research has been undertaken in the dog. It is hoped that this review spurs further research into the etiopathogenic factors in canine KCS.

Primary Sjogren's syndrome: current and prospective therapies

OBJECTIVE

To summarize data on existing and experimental therapies for primary Sjogren's syndrome (pSS), referring both to sicca syndrome and to other systemic disease manifestations.

METHODS

Relevant English and non-English articles acquired through Medline were reviewed.

RESULTS

pSS usually has a benign clinical course, centered on sicca features and general musculoskeletal manifestations, and is managed symptomatically. However, a subset of patients develops more severe extraglandular disease that warrants close monitoring and aggressive treatment. For dry eyes and mouth, nonpharmacologic measures to preserve secretions, and tear and saliva substitutes, offer some symptomatic relief. Muscarinic agonists and topical cyclosporine yield well-documented improvement in ocular sicca features. Although traditional antirheumatic drugs are used empirically for polyarthritis and other Sjogren's symptoms, their efficacy in pSS overall and as disease-modifying agents is limited. For the potential severe, nonexocrine manifestations complicating pSS, standard high-dose immunosuppression is used. Among the biologic agents already examined in pSS, those targeting tumor necrosis factor (TNF)-alpha failed to demonstrate significant benefit. Nonetheless, rituximab and other B-cell-depleting therapies appear promising.

CONCLUSIONS

Treatment of pSS patients with severe extraglandular disease should differ from that of patients with predominantly sicca features and/or general muscoloskeletal manifestations. pSS treatment is mainly symptomatic, primarily directed against sicca complaints. The traditional anti-rheumatic agents show limited efficacy in the systemic process and use of systemic TNF-alpha inhibitors has been very disappointing. B cell depleting treatments and other newer biologic therapies appear more promising.

Sjögren's syndrome in dermatology

Sjogren's Syndrome (SS) is a systemic autoimmune disease characterized by dry eyes (keratoconjunctivis sicca) and dry mouth (xerostomia). To fulfill diagnostic criteria, patients must have objective signs of dryness on examination and laboratory confirmation of an autoimmune process as evidenced by a positive autoantibody to SS-A antigen or a characteristic lip biopsy. SS may exist as a primary condition or in association with other systemic autoimmune disorders (termed secondary SS) such as rheumatoid arthritis, systemic lupus erythematous (SLE), progressive systemic sclerosis (scleroderma), or dermatomyositis. Exclusions to the diagnosis include pre-existing lymphoma, hepatitis C or HIV infection. Pathogenesis involves both genetic (especially HLA-DR) and environmental factors. Both T-cells and B-cells are involved in the generation of cytokines and chemokines within the glands. The epithelial cells of the glands also play a role in pathogenesis. The dermatologic manifestations range from drynessness (sicca) and its complications to vasculitis. There is a significant overlap in the clinical manifestations, as well as treatment, of SS and SLE. However, SS patients require special attention to the complications of ocular dryness (keratocojunctivitis sicca and blepharitis) and oral dryness (rapid tooth loss and oral candidiasis) SS patients have a markedly increased risk of lymphoma and enlarged lymph nodes or persistently enlarged parotid/submandibular glands that require further evaluation.

Decreased Salivary Flow Rate as a Dipsogenic Factor in Hemodialysis Patients: Evidence from an Observational Study and a Pilocarpine Clinical Trial

Decreased salivary flow rate causes xerostomia (symptoms of oral dryness) in patients who undergo hemodialysis (HD); however, whether it thus contributes to thirst and excess interdialytic weight gain (IDWG) remains undetermined. In the observational study, 3 mo of data of 90 stable HD patients were collected, and sensations of thirst and xerostomia were assessed by 100-mm visual analog scales (VAS). Multivariate analyses revealed that the VAS oral dryness score was an independent determinant for thirst, daily IDWG, and IDWG%. Unstimulated whole salivary flow rate (UWS) was measured in 45 participants and was negatively correlated with VAS oral dryness score (r = -0.690, P <or= 0.001), daily IDWG (r = -0.361, P = 0.016), and daily IDWG% (r = -0.302, P = 0.045). In the interventional trial, the test drug was 5 mg of oral pilocarpine solution or placebo. Sixty hyperdipsic HD patients (IDWG% > 2%/d) were randomly assigned to either the sequence pilocarpine (2 wk)-washout (3 wk)-placebo (2 wk)-washout (2 mo)-placebo (3 mo) or placebo (2 wk)-washout (3 wk)-pilocarpine (2 wk)-washout (2 mo)-pilocarpine (3 mo) with 35 participants completing the trial. During the 2-wk crossover period (the first to seventh weeks), pilocarpine increased UWS and decreased xerostomia and thirst. The IDWG(2d) decreased (by approximately 0.2 kg; P = 0.013) but not IDWG(3d). During the 3-mo interventional period, pilocarpine increased UWS but decreased both IDWG(2d) (by 0.76 kg; P = 0.021) and IDWG(3d) (by 1.07 kg; P = 0.007). It also modestly increased serum albumin and decreased mean BP. Pilocarpine-related adverse effects were generally mild. In conclusion, decreased salivary flow is a dipsogenic factor in HD patients, and pilocarpine can alleviate it.

Lamivudine is not effective in primary Sjögren's syndrome

BACKGROUND

Retroviral infection has been implicated in the pathogenesis of primary Sjögren's syndrome.

OBJECTIVE

To examine the efficacy of the reverse transcriptase inhibitor lamivudine in patients with this syndrome.

METHODS

16 patients with primary Sjögren's syndrome were randomised to receive either lamivudine 150 mg twice daily or placebo for three months. Measures of lacrimal and salivary function, including minor salivary gland biopsies, were obtained before and after treatment.

RESULTS

Treatment with lamivudine did not result in significant improvement in the primary outcome measure of unstimulated whole salivary flow or other secondary measures, including minor salivary gland biopsy focus scores.

CONCLUSION

Lamivudine is not effective in patients with primary Sjögren's syndrome, suggesting either that a retroviral aetiology is not present or that it may be important only in early disease.

Changes in the tear film and ocular surface from dry eye syndrome

Dry eye syndrome (DES) refers to a spectrum of ocular surface diseases with diverse and frequently multiple aetiologies. The common feature of the various manifestations of DES is an abnormal tear film. Tear film abnormalities associated with DES are tear deficiency, owing to insufficient supply or excessive loss, and anomalous tear composition. These categorizations are artificial, as in reality both often coexist. DES disrupts the homeostasis of the tear film with its adjacent structures, and adversely affects its ability to perform essential functions such as supporting the ocular surface epithelium and preventing microbial invasion. In addition, whatever the initial trigger, moderate and severe DES is characterized by ocular surface inflammation, which in turn becomes the cause and consequence of cell damage, creating a self-perpetuating cycle of deterioration. Progress has been made in our understanding of the aetiology and pathogenesis of DES, and these advances have encouraged a proliferation of therapeutic options. This article aims to amalgamate prevailing ideas of DES development, and to assist in that, relevant aspects of the structure, function, and production of the tear film are reviewed. Additionally, a synopsis of therapeutic strategies for DES is presented, detailing treatments currently available, and those in development.

An update of the etiology and management of xerostomia

Salivary gland disease gives rise to salivary gland enlargement, pain, and prolonged xerostomia (dry mouth). Xerostomia is the most common long-standing problem for the majority of affected patients. There are many causes of dry mouth, with long-standing xerostomia being a particular problem in Sjögren's syndrome and after radiation to the head and neck region. Xerostomia is usually managed with saliva substitutes, but a large number of potential systemic therapies of long-standing xerostomia now exist. Some-particularly immunosuppressants-are of fundamental interest for the potential reduction of gland damage in Sjögren's syndrome but as yet are of limited clinical usefulness. Others, particularly pilocarpine and cevimeline, are, or have the potential to be, clinically useful in stimulating salivation by virtue of their action on cholinergic receptors.

Oral pilocarpine for the treatment of keratoconjunctivitis sicca with central corneal irregularity

A 31-year-old female physician with bilateral myopia had unilateral myopic laser in situ keratomileusis in the right eye. The patient was overcorrected with the initial treatment and had 2 subsequent hyperopic treatments, resulting in central corneal irregularity. During the course of treatment, the patient was diagnosed with Sjögren's syndrome with marked keratoconjunctivitis sicca. The patient had anisometropia, aniseikonia, and monocular diplopia and was unable to tolerate contact lenses. Oral pilocarpine (Salagen) was prescribed, which improved salivation, lacrimation, and keratoconjunctivitis sicca. The patient was able to tolerate rigid gas-permeable contact lenses to achieve 20/20 visual acuity in both eyes and regain binocular vision.

Treatment of primary Sjögren's syndrome with low-dose human interferon alfa administered by the oromucosal route: combined phase III results

OBJECTIVE

This study tested the safety and efficacy of human interferon (IFN) alfa for treatment of salivary hypofunction and dry mouth symptoms in primary Sjögren's syndrome patients.

METHODS

Combined results are reported from 2 phase III clinical trials in which a total of 497 subjects with primary Sjögren's syndrome received 150 international units of human IFN alfa or matching placebo 3 times per day for 24 weeks by the oromucosal route.

RESULTS

Subjects given IFN alfa had a significantly (P = 0.01) greater mean increase in unstimulated whole saliva (UWS) flow, compared with subjects given placebo. In IFN alfa patients, increases in UWS correlated positively and significantly with improvements noted in 7 of 8 symptoms associated with oral and ocular dryness. The coprimary endpoints of stimulated whole saliva flow and oral dryness were not significantly improved in the IFN alfa group relative to placebo. No significant differences were found between the groups with respect to overall adverse event incidence or severity.

CONCLUSION

IFN alfa given at low dosage by the oromucosal route can significantly increase UWS flow in patients with primary Sjögren's syndrome, without causing significant adverse events.

Correlação entre o grau de xerostomia e o resultado da sialometria em pacientes com Síndrome de Sjögren

Introdução: Xerostomia é a sensação subjetiva de boca seca, que pode estar associada à várias doenças ou alterações sistêmicas, incluindo a Síndrome de Sjögren. Forma de estudo: Clínico prospectivo. Material e método: Realizamos um estudo com 8 pacientes portadores de Síndrome de Sjögren e que se queixavam de xerostomia. Esses pacientes foram submetidos a um questionário que abordava sinais e sintomas comumente relacionados à xerostomia e realizaram uma sialometria a fim de se tentar estabelecer algum tipo de associação entre ambos (questionário e sialometria). Resultado: Observamos que apenas 3 pacientes apresentaram um fluxo salivar diminuído (anormal), enquanto todos eles referiam sintomas orais, em graus variáveis. Conclusão: Assim, concluímos que a intensidade/quantidade de queixas orais não está diretamente relacionada ao fluxo salivar dos pacientes.

Pharmacotherapy of xerostomia in primary Sjögren's syndrome

We reviewed the current literature concerning the treatment of dry mouth in patients with primary Sjögren's syndrome (SJS). Computerized MEDLINE search engines were used with the terms Sjögren, xerostomia, dry mouth, and treatment. References from key articles were searched, and all pertinent articles were procured and reviewed. Primary SJS is an uncommon but serious disorder. Dry mouth caused by SJS can lead to dental erosion, dysphagia, oral infections, and discomfort. Preventing these complications is of paramount importance. Pharmacotherapy is limited to topical saliva substitutes, which are considered first, followed by muscarinic stimulators such as pilocarpine or cevimeline, if required. Immunosuppressive therapy is being investigated. Patients should have regular oral and dental examinations to detect complications. Satisfaction with the efficacy and tolerability of treatment should be monitored frequently. The clinician may have to use a trial-and-error approach to determine a successful regimen.

Use of muscarinic agonists in the treatment of Sjögren's syndrome

Two muscarinic agonists (pilocarpine and cevimeline) have recently been approved for the treatment of symptoms of xerostomia in Sjögren's syndrome (SS). These agents stimulate the M1 and M3 receptors present on salivary glands, leading to increased secretory function. The use of these agents emphasizes the importance of neuroendocrine mechanisms in SS, which is considered an autoimmune disorder. We review recent studies on the release of cytokines and metalloproteinases in SS-affected glands and their influence on the release of and response to neurotransmitters. Also, we review the structure and function of muscarinic receptors as they may relate to SS and the potential use of novel muscarinic agonists in SS.

The treatment of dry eye

The most widely used therapy for dry eye disease is tear replacement by topical artificial tears. Punctal occlusion to prevent the drainage of natural or artificial tears is the most common non-pharmacological treatment. These and other traditional therapies for dry eye disease are only palliative, however, as they replace or conserve the tears without necessarily correcting the underlying disease process. As our understanding of the pathology of dry eye disease improves, new treatment strategies are being developed. Topical anti-inflammatory and immunomodulatory agents, such as cyclosporin A, are under investigation in the treatment of dry eye, as it is anticipated that they will correct the vicious cycle of inflammation and cell damage on the ocular surface and lacrimal glands.

Xerostomia, xerophthalmia, and plasmacytic infiltrates of the salivary glands (Sjögren's-like syndrome) in a cat

A 2.5-year-old domestic shorthair cat was evaluated because of dysphagia and weight loss of 4 weeks' duration. MIld blepharospasm and conjunctival hyperemia were evident in both eyes, oral mucous membranes were tacky on palpation, and salivary glands were enlarged. Results of a Schirmer tear test were 0 mm/min for both eyes. Administration of atropine did not cause salivation or caused secretion fo thick rope-like saliva. Examination of biopsy specimens of salivary glands revealed a plasmacytic infiltrate. Sjögren's syndrome (SS) was diagnosed. Oral administration of prednisone was instituted but was discontinued after a minimal positive response was evident 6 weeks after initiation of treatment. Palliative treatment with a 6% solution of pilocarpine 4 to 5 times/d, cyclosporine, hylan A, and neomycin-polymyxin-bacitracin ophthalmic ointment resulted in clinical improvement in the cat. Although reported rarely in animals, SS may be more common than currently is recognized. Most treatment regimens for SS are aimed at alleviating clinical signs.

Tear secretion by lacrimal glands in transgenic mice lacking water channels AQP1, AQP3, AQP4 and AQP5

The expression of three aquaporin (AQP)-type water channels has been reported in the lacrimal gland: AQP5 in the apical membranes of acinar and duct cells, AQP4 in the basolateral membranes of acinar cells, and AQP1 in microvascular endothelia. Recent experiments indicate that water movement through AQP5 in the salivary gland is important in saliva secretion. To investigate the role of aquaporins in lacrimal gland function, basal and pilocarpine-stimulated tear secretion was compared in wildtype mice and knockout mice lacking AQP1, AQP4 and AQP5, as well as AQP3, which was found here to be expressed in the basolateral membrane of acinar cells. Tear fluid was collected in anesthetized mice using microcapillary tubes before and at 4 min intervals after pilocarpine administration. Tear fluid volumes were (in microliter per 4 min, S.E.): 0.69 +/- 0.06 (wildtype mice), 0.70 +/- 0.07 (AQP1 -/-), 0.81 +/- 0.13 (AQP3 -/-), 0.62 +/- 0.14 (AQP4 -/-), and 0.78 +/- 0.09 (AQP5 -/-) (differences not significant). Chloride concentrations (average 155 +/- 13 mM) measured by a fluorescence assay were also not different in tear fluid collected from wildtype vs aquaporin null mice. These findings provide direct evidence against an essential role for aquaporins in lacrimal gland fluid secretion. The requirement for aquaporins in salivary but not lacrimal gland secretion, may involve the substantially slower fluid secretion rate across lacrimal gland acinar cells.

The use of oral pilocarpine in xerostomia and Sjögren's syndrome

OBJECTIVES

To analyze the role of oral pilocarpine in the treatment of xerostomia of Sjogren's syndrome (SS).

METHODS

The medical literature was reviewed for all studies using oral pilocarpine to treat xerostomia caused by SS or radiotherapy registered in the MedLine Silver Platter database from 1966 to 1998.

RESULTS

All the studies identified excluded elderly individuals with cardiac or pulmonary disease. Patients with postradiation xerostomia and incomplete resection of the salivary glands were more likely to benefit from oral pilocarpine when there was sufficient residual glandular function than patients with radical surgery for head and neck cancer (HNC). However, patients with SS and other inflammatory disorders seemed to benefit from oral pilocarpine, when compared with patients with postradiation xerostomia. The optimal dose of oral pilocarpine, which was less likely to cause side effects, was 5 mg four times daily. A recent multi-center study in SS patients suggests that oral pilocarpine is effective and safe for long-term administration. Although some studies did not show evidence for increased salivary gland secretion rate as measured by sialometry, symptoms improved, perhaps because of increased secretion from the minor salivary glands or better conditioning of the oral mucosa.

CONCLUSIONS

Oral pilocarpine is likely to benefit patients with SS by reducing the symptoms of xerostomia, even if the salivary gland secretion rate does not increase. Further controlled studies are needed in patients with SS and should include elderly patients with cardiovascular disease treated with moderate doses of oral pilocarpine.