Funding for this research was provided by:
German Federal Ministry of Education and Research (BMBF FKZ 01ET0713, 01ET1003A, 01GI0882)
Received: 7 December 2016
Accepted: 10 January 2018
First Online: 6 February 2018
Ethics approval and consent to participate
: The KORA-Age study was approved by the Ethics Committee of the Bavarian Medical Association, written informed consent has been obtained from all participants and the investigations have been conducted according to the principles expressed in the Declaration of Helsinki.
: Not applicable.
: The authors declare that they have no competing interests.
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