The Northern Finland Birth Cohort Eye Study: Design and baseline characteristics

Peer reviewe

Itäsuomenkarjan kantakirja-analyysi vuosilta 1900-1911

Tutkimuksessa on koottu käytettävissä olleiden itäsuomenkarjan ensimmäisiin kantakirjoihin hyväksyttyjen eläinten tietoja. Tiedot koottiin julkaistavaan ja helposti jaettavaan muotoon Excel-taulukkoon. Aineistona näille tiedoille oli käytössä itäsuomalaiselle maatiaiskarjalle tarkoitettuja kantakirjoja vuosilta 1900-1911. Analysoitavana oli tietoja eläinten lukumääristä, sijainneista, värityksistä, sarvellisuudesta, ruumiin mitoista ja tuotannosta maidon määrästä sekä rasvapitoisuudesta. Kerätyistä tiedoista muodostettiin keskiarvot sisältäviä tai tietojen jakautumista kuvaavia kaavioita, joiden tuloksia analysoitiin ja vertailtiin aikakauden tilanteeseen ja moderniin rodun edustukseen. Työn toimeksiantajana toimi Suomen Alkuperäiskarja Ry. Työssä on kartoitettu itäsuomenkarjan historiaa rodun erkaantumisesta muusta suomenkarjasta alkaen, käsittelyssä olleiden kantakirjojen ajalta ja parikymmentä vuotta siitä eteenpäin. Kartoituksen yhteydessä on koottu myös helposti saatavilla olevaa tietoa itäsuomenkarjan nykytilanteesta ja käyty läpi pienimuotoisesti viime vuosien kehitystä. Tulosten perusteella voidaan sanoa, että itäsuomenkarjan jalostuksen ensimmäisen vuosikymmenen aikana saatiin positiivisia tuloksia jalostukselle määrättyyn suuntaan nähden. Kantakirjattujen eläinten määrä lisääntyi, populaation tyyppi vakiintui ulkonäköseikkojen ja mittaustulosten osalta sekä lehmien keskimääräinen maidontuotanto ja rasvapitoisuus kasvoivat. Ensimmäisen vuosikymmenen aikana itäsuomenkarjan jalostus edisti esimerkillään karjanjalostustyötä sen alkuvaiheilla muidenkin rotujen kannalta. Opinnäytetyö on jatkoa Jaana Juvanin aloittamalle työlle kartoittaa ja analysoida suomenkarjan rotujen vanhojen kantakirjojen tietoja. Juvani on tehnyt vastaavan analyysin pohjoissuomenkarjan kantakirjoista 2014.The purpose of this study was to gather information from the first herdbooks for Eastern Finncattle (EFC). Data was compiled in a format that could be published and easily distributed in an Excel-sheet. This information is based on 8 herdbooks during 1900-1911 and contains info about the cattle such as location, appearance, body measurements and milk production. From the collected data diagrams containing averages were developed. A map was put together based on locations. In the analysis, data from the EFC was compared to other cattle from that era and to modern breed representation. The client of this thesis was Suomen Alkuperäiskarja Ry. The beginning history for the Eastern Finncattle was studied. It starts when Finnish native breed of cattle separated into three different types of cattle, going over the first decade that includes herdbooks studied and ending about twenty years after the last analysed herdbook. There is also a compilation that consists of present day information for EFC during the last decade. During the first decade of breeding EFC the results were positive, based on the direction for cattle breeding which was outlined in the beginning. The number of animals that were included in herdbooks increased, the appearance of the cattle had started to even out both in colour and body measurements and the cows average milk production and fat content increased. These results inspired and promoted cattle breeding also in other cattle breeds during this first decade. The thesis is a continuation of the work started by Jaana Juvani in mapping and analysing data from old herdbooks on Finnish cattle breeds

Comparative studies in the Northern Finland Birth Cohort eye study

Abstract Population-based studies in ophthalmology gather information on a variety of ocular findings. Thanks to these studies, we are aware of, for example, the changes in refraction during the life course, and we know the mean and range of the measurements of different features of ocular anatomy and the prevalences of certain ocular pathologies. In order to gather information, different examination methods are used. Some of the methods may be time-consuming and require sophisticated equipment. Therefore, these methods need to be evaluated so that research may be performed most efficiently without jeopardising quality. The aim of this thesis is to evaluate examination methods regarding 1) the evaluation of refraction and visual acuity, 2) the assessment of intraocular pressure with three different devices, and 3) the evaluation of the parameters of retinal nerve fiber layer and optic nerve head with three imaging devices. Additionally, this thesis gives information on the ocular features mentioned above. The subjects of three of the publications were members of the NFBC1966, Northern Finland Birth Cohort 1966. The current eye study was conducted in conjunction with the 46-year follow-up of the NFBC. A total of 10 321 cohort members living in Finland were randomised and 3 070 (60% of the eye screening group responded) were included in the eye study. The subjects of one of the publications were members of the Northern Finland Birth Cohort 1986. Our study showed that visual acuity and refraction can be evaluated relatively reliably with an autorefractometer, but the method may not be optimal when best corrected visual acuity is in a crucial role. The results of rebound tonometer iCare correlate well with the reference standard, Goldmann applanation tonometer, but they should not be used interchangeably. The results of rebound tonometers iCare TA01i and iCare IC100 are close to each other, and iCare IC100 is suitable for use in large screening studies. When comparing the parameters obtained with OCT, HRT and GDx, the correlation is high for cup and disc parameters of OCT and HRT, but substantially lower for retinal nerve fiber layer, image quality and glaucoma detection parameters.Tiivistelmä Oftalmologiset väestötutkimukset keräävät tietoa erilaisista silmälöydöksistä. Näiden tutkimusten ansiosta tiedämme esimerkiksi, miten taitteisuus muuttuu iän myötä, useiden silmän anatomisten ominaisuuksien keskiarvon ja vaihteluvälin sekä erilaisten silmäsairauksien ilmaantuvuuden. Tiedon keräämiseen käytetään erilaisia tutkimuslaitteita ja -menetelmiä. Jotkut tutkimukset voivat vaatia paljon aikaa ja edellyttää monimutkaista välineistöä. Tutkimusmenetelmien arvioiminen on tärkeää, jotta tutkimustiedon kerääminen olisi mahdollisimman sujuvaa ja tehokasta laadun kärsimättä. Tämän tutkimuksen tarkoitus on tarkastella tutkimusmenetelmiä liittyen 1) silmän taitteisuuden ja näöntarkkuuden tutkimiseen, 2) silmänpaineen mittaamiseen ja 3) hermosäiekerroksen ja näköhermonpään mittojen vertaamiseen kolmella kuvantamislaitteella. Lisäksi tämä tutkimus antaa tietoa edellä mainituista silmälöydöksistä keski-ikäisellä kaukasialaisella väestöllä. Kolmen osajulkaisun tutkimusväestö kuului pohjoissuomalaiseen vuoden 1966 syntymäkohorttiin. Silmätutkimus toteutettiin syntymäkohortin 46-vuotistutkimuksen yhteydessä. 10321 Suomessa asuvaa kohortin jäsentä satunnaistettiin ja silmätutkimukseen osallistui 3070 henkilöä eli 60 % kutsutuista. Yhden osajulkaisun tutkimusväestö kuului pohjoissuomalaiseen vuoden 1986 syntymäkohorttiin. Tutkimuksemme osoitti, että silmän taitteisuutta ja näöntarkkuutta voidaan tutkia autorefraktometrillä varsin luotettavasti. Laitteen tulos ei kuitenkaan ole riittävän luotettava tilanteissa, joissa parhaalla korjatulla näöntarkkuudella on ratkaiseva merkitys. Kimmoketonometri iCaren tulokset korreloivat hyvin referenssistandardin eli Goldmannin applanaatiotonometrin tulosten kanssa, mutta niitä ei voi pitää keskenään vaihtokelpoisina. Kimmoketonometrien iCareTA01i ja iCare IC100 tulokset ovat lähellä toisiaan, ja myös iCare IC100 -mittari soveltuu käytettäväksi laajoissa seulontatutkimuksissa. Verratessa OCT:n, HRT:n ja GDx:n parametreja näköhermonpään kokoon ja keskuskuoppaan liittyvät OCT:n ja HRT:n parametrit korreloivat keskenään hyvin, kun taas korrelaatio hermosäiekerroksen, kuvan laadun ja glaukoomadiagnostiikan parametrien välillä on huomattavasti huonompi

Evaluating refraction and visual acuity with the Nidek autorefractometer AR-360A in a randomized population-based screening study

Abstract Purpose: The evaluation of visual acuity (VA) and refraction in the Northern Finland Birth Cohort Eye study was performed using the Nidek AR-360A autorefractometer. The accuracy of the method for this population-based screening study was assessed. Methods: Measurements of the refractive error were obtained from the right eyes of 1238 subjects (mean age 47), first objectively with the AR-360A and then subjectively by an optometrist. Agreement with the subjective refraction was calculated for sphere, cylinder, mean spherical equivalent (MSE), cylindrical vectors J₄₅ and J₀ and presbyopic correction (add). Visual acuity (VA) was measured using an ETDRS chart and the autorefractometer. Results: The refractive error measured with the AR-360A was higher than the subjective refraction performed by the optometrist for sphere (0.007 D ± 0.24 D p = 0.30) and also for cylinder (−0.16 D ± 0.20 D p < 0.0005). The bias between the measurements of MSE, J₄₅ and J₀ was low: −0.07 D ± 0.22 D (p = 0.002), 0.01 D ± 0.43 D (p = 0.25) and −0.01 D ± 0.42 D (p = 0.43), respectively. The amount of add measured by the autorefractometer was higher than the subjective 0.35 D ± 0.29 D (p < 0.0005). There was a statistically significant correlation between VA (p < 0.0005) and the difference between the subjective and objective refraction. In 99.2% of the measurements, visual values were within one decimal line of each other. Conclusion: The Nidek AR-360A autorefractometer is an accurate tool for determining the refraction and VA in a clinical screening trial

Correlation of iCare ic100 tonometry with iCare TA01i in screening of unselected population in Northern Finland Birth Cohort Eye study

Abstract Purpose: iCare tonometers are easy-to-use and portable devices for measuring the intraocular pressure (IOP). Purpose was to evaluate the IOP values measured by both novel iCare ic100 and conventional model TA01i devices in unselected population. Methods: IOP was measured with iCare ic100 and TA01i tonometers in 149 participants aged 32–33 years (born in 1985 or 1986) of the Northern Finland Birth Cohort Eye 2 study. The right eye of each participant was selected for analysis. We also collected data on axial length, corneal curvature and central corneal thickness (CCT). Bland-Altman plot was used for comparing the values obtained by these devices. Results: Mean IOP measured with the ic100 device was 13.8 (3.4) mmHg, with TA01i it was 12.5 (3.0) mmHg. The mean difference between these devices was 1.30 mmHg (p < 0.001) and R² was 0.694. In Bland-Altman analysis, the agreement between the two tonometers ic100 and TA01i was constantly good (mean difference −1.30, ic100 device showing higher measures). There was a correlation between IOP and CCT (r = 0.269, p < 0.001 for ic100 and r  = 0.255, p  = 0.002 for TA01i), but not with IOP and corneal curvature or IOP and axial length. Conclusions: In summary, we found ic100 rebound tonometry to be both reliable and effective, although CCT may influence IOP measurements with ic100 and TA01i. Therefore, iCare ic100 is suitable for IOP measurement in large cohort studies

Comparison of imaging parameters between OCT, GDx and HRT in the Northern Finland birth cohort eye study

Abstract Purpose: The purpose of the study was to assess and compare the optic nerve head (ONH) and retinal nerve fibre layer (RNFL) parameters and image quality parameters obtained by Cirrus HD-OCT, GDxECC and HRT3 in a population-based screening study. Methods: This analysis examined 2566 subjects taking part in the Northern Finland Birth Cohort Eye study. Images with spectral domain OCT (Cirrus HD-OCT 4000), scanning laser ophthalmoscopy (HRT3) and scanning laser polarimetry (GDxECC) were obtained from each subject. The correlation of average and regional parameters of RNFL and ONH between devices was evaluated. Results: The RNFL thickness was 90.9 µm when measured with OCT, 24.6 µm with HRT and 48.1 µm with GDx. There was a high correlation between the disc and cup measurements with the HRT and OCT and the RNFL thickness of the OCT and GDx (r > 0.5). A statistically significant correlation was found between RNFL measurements of the HRT and OCT in the superior, temporal and inferior quadrants. Optical coherence tomography (OCT) signal strength correlated with the image quality parameters of the HRT and GDx. The percentage of good quality images was the lowest with the GDx. Conclusions: The RNFL thickness in Northern Finland birth cohort was at a lower level compared to other studies. The study confirms the difference in measuring ONH parameters between the imaging devices. However, significant correlations between devices were found in the cup volume and cup disc area ratio parameters of the OCT and HRT. The correlations between image quality parameters and glaucoma detection parameters were relatively low

Combined structure–function analysis in glaucoma screening

Abstract Aim: To assess the applicability of a structure–function (S-F) analysis combining spectral-domain optical coherence tomography (SD-OCT) and standard automated perimetry (SAP) in glaucoma screening in a middle-aged population. Methods: A randomised sample of 3001 Caucasian participants aged 45–49 years of the Northern Finland Birth Cohort Eye Study was examined. We performed an eye examination, including 24–2 SAP, optic nerve head (ONH) and retinal nerve fibre layer (RNFL) photography and SD-OCT of the peripapillary RNFL. The S-F report was generated by Forum Glaucoma Workplace software. OCT, SAP and the S-F analysis were evaluated against clinical glaucoma diagnosis, that is, the positive ‘2 out of 3’ rule based on the clinician’s evaluation of ONH and RNFL photographs and visual fields (VFs). Results: At a specificity of 97.5%, the sensitivity for glaucomatous damage was 26% for abnormal OCT, 35% for SAP and 44% for S-F analysis. Estimated areas under the curve were 0.74, 0.85 and 0.76, and the corresponding positive predictive values were 8 %, 10% and 12%, respectively. By applying a classification tree approach combining OCT, SAP and defect localisation data, a sensitivity of 77% was achieved at 90% specificity. In a localisation analysis of glaucomatous structural and functional defects, the correlation with glaucoma increased significantly if the abnormal VF test points were located on borderline or abnormal OCT zones. Conclusions: SAP performs slightly better than OCT in glaucoma screening of middle-aged population. However, the diagnostic capability can be improved by S-F analysis