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Dry eye symptoms in patients andnormals

Patients with primary-SS may present alarge variety of eye symptoms (V). Someof the most frequently reported and theircorrelation to primary-SS and other con-nective tissue diseases accompanied byKCS as well as in control subjects areshown in Fig. 2.

The large variety and high frequencyof dry eye symptoms in patients with pri-mary-SS shows that it is a very trouble-some condition, constantly affecting thepatients (V). However, results also showthat the symptoms normally ascribed tothe presence of dry eye problems arerather unspecific and may also frequentlybe reported by ordinary people. Thus inpersons aged 30–60 years living in Cop-enhagen City as many as 24% reportedeye symptoms (Fig. 3; VI). These resultsare similar to the findings of a Swedishstudy of persons aged 52–72 years, wherethe frequency of dry eyes and/or drymouth symptoms was 35% (Jacobsson etal. 1989) and also in a recent study com-prising 341 subjects dry eye symptomswere reported by as much as 24% (Hayet al. 1998). In general, women had morecomplaints than men; in particular thefeeling of eye dryness was more commonin women (VI). An increase in symptomswith age might have been expected due tothe effect of hormonel changes and age-ing processes, but was in fact only slightand not significant (VI). In most cases nocorrelation could be established betweenocular symptoms and the presence ofKCS or another ocular surface disease(VI). Results are thus consistent with astudy by Schein et al. (1997) comprisingpersons aged 65 years or more, it was alsoconcluded that symptoms of ocular irri-tation are common, and are only weaklyassociated with pathological results ofthe Schirmer test and Rose bengal score.Also in a study by Hay et al. (1998) thecorrelation between symptoms and objec-tive signs of dry eye was poor, though dryeye examination was restricted to theSchirmer-1 test.

Using questionnaires for screeningpurposes requires a high correlation be-tween symptoms and objective findings,and the use of dry eye questions to dis-cover the presence of KCS and primary-SS seems therefore of limited value. Only

Fig 2. The frequency of eye symptoms (see the questionnaire in Table 2 part B) often reported bydry eye patients. Data are from patients with primary Sjögren’s syndrome (in this figure desig-nated 10SS), patients with other immune inflammatory connective tissue diseases (CTD) andcontrol individuals (N). With keratoconjunctivitis sicca: πKCS. Without keratoconjunctivitis sic-ca: – KCS. Data are from publication V.

complaints about ‘‘a sensation of burningor smarting eyes several times a weeklasting more than half-an-hour’’ was sig-nificantly correlated to the presence ofKCS, and also seemed to be the dry eye

symptom which best predicted the pres-ence of KCS (VI). Analogously, the oralsymptom which best predicted KCS wascomplaints about ‘‘suffering several timesa day from a feeling of dry mouth during

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Fig. 3. The frequency of some of the most frequent dry eye symptoms in a population of 504persons aged 30–60 years from Copenhagen City. Data are modified from publication VI.

the last three months’’ (VI). The symp-toms best predicting primary-SS couldnot be established because of small num-bers and because symptoms are includedin the diagnostic battery of the prelimi-nary European criteria.

According to the Japanese criteria(Homma et al. 1986) diagnosis of pri-mary-SS can be made only in patientswho have overt dry eye or dry mouthsymptoms as a prerequisite. This attitudemay seem reasonable in the sense thatprimary-SS is a disease affecting primar-ily the quality of life and only personswho feel ill should therefore be diag-nosed. However, in patients who havebeen affected by primary-SS very early inlife complaints are rare, as if they have‘‘forgotten’’ how a normal mucus mem-brane feels (Manthorpe et al. 1986), anddiagnosis should be made also in thesecases, irrespectively of symptoms, in or-der to prevent the damaging influence oflong-lasting dry eye and xerostomia, andto ensure early treatment of systemiccomplications, thereby improving thequality of life also in the long run.

In the preliminary European criteriasymptoms of dryness are not a requestbut are included on equal terms with theobjective tests (Table 6) and a person withsymptoms of ocular and oral drynesstherefore already fulfils the criteria forprimary-SS half-way. The poor corre-lation between symptoms and objectivefindings makes it therefore difficult to de-limit which persons should be furthertested, causing needless worry to the pa-tients, and unnecessary and expensive ex-aminations to society. Such consider-ations were the reason for not includingsymptoms in the Copenhagen criteria(Table 6).

The many dry eye symptoms in appar-ently normal, healthy persons are diffi-cult to explain. Part of the explanationis probably that most of the symptomsexperienced by Sjögren patients are alsofrequent in ordinary people, but withmuch lesser severity. Grading the severityof symptoms is, however, almost imposs-ible due to differences in threshhold. Themany complaints discovered may how-ever, also be a realistic problem. Thus in

the population study by Jacobsson et al.(1992) the symptomatic group actuallyhad reduced values for sialometry andtear film break-up time as well as higherlevels of SS-A and SS-B antibodies com-pared to the no-symptoms group. Themany dry eye symptoms discovered in thepresent study may also be a problemespecially of people living in urban areas.Air pollution and living or working indry and dusty environments surroundedby printers and copiers may thus give riseto a reversible dry eye condition called‘‘the office eye syndrome’’, ‘‘pollutionkeratoconjunctivitis’’ or the ‘‘sick build-ing syndrome’’ (Franck 1986 and 1991;Norn 1992). It has also been demon-strated (Prause, unpublished data) thatwhen folding copying paper small par-ticles are liberated which temporarilymay ruin the stability of the tear film witha decrease in tear film break-up time andearly dry spot formation, which is knownto give symptoms of ocular discomfort(Lemp et al. 1971). Since the disturbingeffect on the tear film is caused by en-vironmental factors, and as such a revers-ible condition, the problem may, however,not be detectable when the patients areexamined in other surroundings such asthe room of the ophthalmologist, andthese patients may therefore give rise toconsiderable differential diagnostic prob-lems to the general practitioners and oph-thalmologists. The problem may alsolead to the uncritical use of tear substi-tutes, especially since tear substitutes maybe purchased without prescription, caus-ing unnecessary problems with allergy orintolerance towards preservatives. This isunfortunate since the same tear preserv-atives are used in almost all eye drops in-cluding those for more severe eye dis-eases.

To sum up, most of the symptoms typ-ically reported by dry eye patients arevery common also in persons with nosigns of KCS or other ocular surface dis-eases. Using questionnaires to screen forKCS and primary-SS seems therefore oflimited use and the inclusion of symp-toms in the diagnostic criteria for KCSand primary-SS is also highly question-able.